Address review comments @nalexander

`CacheDirection` enum is used only on the Android side to provide a usable interface. FFI calls are more explicit.

Tests ensure that a cached query is faster than the uncached one.

ffi/src/lib.rs

@@ -87,11 +87,12 @@ use std::vec;
 
 pub use mentat::{
     Binding,
+    CacheDirection,
     Entid,
     FindSpec,
     HasSchema,
+    InProgress,
     KnownEntid,
-    Keyword,
     Queryable,
     QueryBuilder,
     QueryInputs,
@@ -126,6 +127,7 @@ pub use utils::strings::{
 
 pub use utils::log;
 
+// type aliases for iterator types.
 pub type BindingIterator = vec::IntoIter<Binding>;
 pub type BindingListIterator = std::slice::Chunks<'static, mentat::Binding>;
 
@@ -221,6 +223,13 @@ impl<T, E> From<Result<T, E>> for ExternResult where E: std::error::Error {
     }
 }
 
+#[repr(C)]
+#[derive(Debug)]
+pub struct InProgressTransactResult<'a, 'c> {
+    pub in_progress: *mut InProgress<'a, 'c>,
+    pub result: *mut ExternResult,
+}
+
 /// A store cannot be opened twice to the same location.
 /// Once created, the reference to the store is held by the caller and not Rust,
 /// therefore the caller is responsible for calling `destroy` to release the memory
@@ -247,17 +256,737 @@ pub extern "C" fn store_open(uri: *const c_char) -> *mut Store {
 
 // TODO: begin_read
 
-// TODO: begin_transaction
+/// Starts a new transaction to allow multiple transacts to be
+/// performed together. This is more efficient than performing
+/// a large set of individual commits.
+///
+/// Returns as [Result<TxReport>](mentat::TxReport) as an [ExternResult](ExternResult).
+///
+/// # Safety
+///
+/// Callers must ensure that the pointer to the [Store](mentat::Store) is not dangling.
+///
+/// Callers are responsible for managing the memory for the return value.
+/// A destructor `tx_report_destroy` is provided for releasing the memory for this
+/// pointer type.
+///
+/// TODO: Document the errors that can result from begin_transaction
+#[no_mangle]
+pub unsafe extern "C" fn store_begin_transaction(store: *mut Store) -> *mut ExternResult {
+    let store = &mut*store;
+    Box::into_raw(Box::new(store.begin_transaction().into()))
+}
 
-/// Performs a single transaction against the store.
+/// Perform a single transact operation using the current in progress
+/// transaction. Takes edn as a string to transact.
+///
+/// Returns as [Result<TxReport>](mentat::TxReport) as an [ExternResult](ExternResult).
 ///
 /// # Safety
 ///
 /// Callers are responsible for managing the memory for the return value.
-/// A destructor `destroy` is provided for releasing the memory for this
+/// A destructor `tx_report_destroy` is provided for releasing the memory for this
 /// pointer type.
 ///
-// TODO: Document the errors that can result from transact
+/// TODO: Document the errors that can result from transact
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_transact<'m>(in_progress: *mut InProgress<'m, 'm>, transaction: *const c_char) -> *mut ExternResult {
+    let in_progress = &mut*in_progress;
+    let transaction = c_char_to_string(transaction);
+    Box::into_raw(Box::new(in_progress.transact(transaction).into()))
+}
+
+/// Commit all the transacts that have been performed using this
+/// in progress transaction.
+///
+/// Returns as [Result<()>](std::result::Result) as an [ExternResult](ExternResult).
+///
+/// TODO: Document the errors that can result from transact
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_commit<'m>(in_progress: *mut InProgress<'m, 'm>) -> *mut ExternResult {
+    let in_progress = Box::from_raw(in_progress);
+    Box::into_raw(Box::new(in_progress.commit().into()))
+}
+
+/// Rolls back all the transacts that have been performed using this
+/// in progress transaction.
+///
+/// Returns as [Result<()>](std::result::Result) as an [ExternResult](ExternResult).
+///
+/// TODO: Document the errors that can result from rollback
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_rollback<'m>(in_progress: *mut InProgress<'m, 'm>) -> *mut ExternResult {
+    let in_progress = Box::from_raw(in_progress);
+    Box::into_raw(Box::new(in_progress.rollback().into()))
+}
+
+/// Creates a builder using the in progress transaction to allow for programmatic
+/// assertion of values.
+///
+/// # Safety
+///
+/// Callers are responsible for managing the memory for the return value.
+/// A destructor `in_progress_builder_destroy` is provided for releasing the memory for this
+/// pointer type.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder<'m>(in_progress: *mut InProgress<'m, 'm>) -> *mut InProgressBuilder {
+    let in_progress = Box::from_raw(in_progress);
+    Box::into_raw(Box::new(in_progress.builder()))
+}
+
+/// Creates a builder for an entity with `tempid` using the in progress transaction to
+/// allow for programmatic assertion of values for that entity.
+///
+/// # Safety
+///
+/// Callers are responsible for managing the memory for the return value.
+/// A destructor `entity_builder_destroy` is provided for releasing the memory for this
+/// pointer type.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_entity_builder_from_temp_id<'m>(in_progress: *mut InProgress<'m, 'm>, temp_id: *const c_char) -> *mut EntityBuilder<InProgressBuilder> {
+    let in_progress = Box::from_raw(in_progress);
+    let temp_id = c_char_to_string(temp_id);
+    Box::into_raw(Box::new(in_progress.builder().describe_tempid(&temp_id)))
+}
+
+/// Creates a builder for an entity with `entid` using the in progress transaction to
+/// allow for programmatic assertion of values for that entity.
+///
+/// # Safety
+///
+/// Callers are responsible for managing the memory for the return value.
+/// A destructor `entity_builder_destroy` is provided for releasing the memory for this
+/// pointer type.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_entity_builder_from_entid<'m>(in_progress: *mut InProgress<'m, 'm>, entid: c_longlong) -> *mut EntityBuilder<InProgressBuilder> {
+    let in_progress = Box::from_raw(in_progress);
+    Box::into_raw(Box::new(in_progress.builder().describe(&KnownEntid(entid))))
+}
+
+/// Starts a new transaction and creates a builder using the that transaction
+/// to allow for programmatic assertion of values.
+///
+/// # Safety
+///
+/// Callers are responsible for managing the memory for the return value.
+/// A destructor `in_progress_builder_destroy` is provided for releasing the memory for this
+/// pointer type.
+#[no_mangle]
+pub unsafe extern "C" fn store_in_progress_builder(store: *mut Store) -> *mut ExternResult {
+    let store = &mut*store;
+    let result = store.begin_transaction().and_then(|in_progress| {
+        Ok(in_progress.builder())
+    });
+    Box::into_raw(Box::new(result.into()))
+}
+
+/// Starts a new transaction and creates a builder for an entity with `tempid`
+/// using the that transaction to allow for programmatic assertion of values for that entity.
+///
+/// # Safety
+///
+/// Callers are responsible for managing the memory for the return value.
+/// A destructor `entity_builder_destroy` is provided for releasing the memory for this
+/// pointer type.
+#[no_mangle]
+pub unsafe extern "C" fn store_entity_builder_from_temp_id(store: *mut Store, temp_id: *const c_char) -> *mut ExternResult {
+    let store = &mut*store;
+    let temp_id = c_char_to_string(temp_id);
+    let result = store.begin_transaction().and_then(|in_progress| {
+        Ok(in_progress.builder().describe_tempid(&temp_id))
+    });
+    Box::into_raw(Box::new(result.into()))
+}
+
+/// Starts a new transaction and creates a builder for an entity with `entid`
+/// using the that transaction to allow for programmatic assertion of values for that entity.
+///
+/// # Safety
+///
+/// Callers are responsible for managing the memory for the return value.
+/// A destructor `entity_builder_destroy` is provided for releasing the memory for this
+/// pointer type.
+#[no_mangle]
+pub unsafe extern "C" fn store_entity_builder_from_entid(store: *mut Store, entid: c_longlong) -> *mut ExternResult {
+    let store = &mut*store;
+    let result = store.begin_transaction().and_then(|in_progress| {
+        Ok(in_progress.builder().describe(&KnownEntid(entid)))
+    });
+    Box::into_raw(Box::new(result.into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/string`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_add_string<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: *const c_char) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = c_char_to_string(value).into();
+    Box::into_raw(Box::new(builder.add_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/long`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_add_long<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::Long(value);
+    Box::into_raw(Box::new(builder.add_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If `value` is not present as an Entid in the store.
+/// If the type of `kw` is not `:db.type/ref`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_add_ref<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::Ref(value);
+    Box::into_raw(Box::new(builder.add_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If `value` is not present as an attribute in the store.
+/// If the type of `kw` is not `:db.type/keyword`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_add_keyword<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: *const c_char) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = kw_from_string(c_char_to_string(value)).into();
+    Box::into_raw(Box::new(builder.add_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/boolean`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_add_boolean<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: bool) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.add_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/double`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_add_double<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: f64) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.add_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/instant`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_add_timestamp<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::instant(value);
+    Box::into_raw(Box::new(builder.add_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/uuid`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_add_uuid<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: *mut [u8; 16]) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value = &*value;
+    let value = Uuid::from_bytes(value).expect("valid uuid");
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.add_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/string`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_retract_string<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: *const c_char) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = c_char_to_string(value).into();
+    Box::into_raw(Box::new(builder.retract_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/long`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_retract_long<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::Long(value);
+    Box::into_raw(Box::new(builder.retract_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/ref`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_retract_ref<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::Ref(value);
+    Box::into_raw(Box::new(builder.retract_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/keyword`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_retract_keyword<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: *const c_char) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = kw_from_string(c_char_to_string(value)).into();
+    Box::into_raw(Box::new(builder.retract_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/boolean`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_retract_boolean<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: bool) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.retract_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/double`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_retract_double<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: f64) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.retract_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/instant`.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_retract_timestamp<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::instant(value);
+    Box::into_raw(Box::new(builder.retract_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/uuid`.
+///
+/// TODO don't panic if the UUID is not valid - return result instead.
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_retract_uuid<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>, entid: c_longlong, kw: *const c_char, value: *mut [u8; 16]) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value = &*value;
+    let value = Uuid::from_bytes(value).expect("valid uuid");
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.retract_kw(KnownEntid(entid), &kw, value).into()))
+}
+
+/// Transacts and commits all the assertions and retractions that have been performed
+/// using this builder.
+///
+/// This consumes the builder and the enclosed [InProgress](mentat::InProgress) transaction.
+///
+/// Returns as [Result<()>(std::result::Result) as an [ExternResult](ExternResult).
+///
+/// TODO: Document the errors that can result from transact
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_commit<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>) -> *mut ExternResult {
+    let builder = Box::from_raw(builder);
+    Box::into_raw(Box::new(builder.commit().into()))
+}
+
+/// Transacts all the assertions and retractions that have been performed
+/// using this builder.
+///
+/// This consumes the builder and returns the enclosed [InProgress](mentat::InProgress) transaction
+/// inside the [InProgressTransactResult](mentat::InProgressTransactResult) alongside the [TxReport](mentat::TxReport) generated
+/// by the transact.
+///
+/// # Safety
+///
+/// Callers are responsible for managing the memory for the return value.
+/// The destructors `in_progress_destroy` and `tx_report_destroy` arew provided for
+/// releasing the memory for these pointer types.
+///
+/// TODO: Document the errors that can result from transact
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_transact<'a, 'c>(builder: *mut InProgressBuilder<'a, 'c>) -> *mut InProgressTransactResult<'a, 'c> {
+    let builder = Box::from_raw(builder);
+    let (in_progress, tx_report) = builder.transact();
+    let result = InProgressTransactResult { in_progress: Box::into_raw(Box::new(in_progress)), result: Box::into_raw(Box::new(tx_report.into())) };
+    Box::into_raw(Box::new(result))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/string`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_add_string<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: *const c_char) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = c_char_to_string(value).into();
+    Box::into_raw(Box::new(builder.add_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/long`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_add_long<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::Long(value);
+    Box::into_raw(Box::new(builder.add_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/ref`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_add_ref<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::Ref(value);
+    Box::into_raw(Box::new(builder.add_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/keyword`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_add_keyword<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: *const c_char) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = kw_from_string(c_char_to_string(value)).into();
+    Box::into_raw(Box::new(builder.add_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/boolean`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_add_boolean<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: bool) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.add_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/double`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_add_double<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: f64) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.add_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/instant`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_add_timestamp<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::instant(value);
+    Box::into_raw(Box::new(builder.add_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to assert `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/uuid`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_add_uuid<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: *mut [u8; 16]) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value = &*value;
+    let value = Uuid::from_bytes(value).expect("valid uuid");
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.add_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/string`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_retract_string<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: *const c_char) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = c_char_to_string(value).into();
+    Box::into_raw(Box::new(builder.retract_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/long`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_retract_long<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::Long(value);
+    Box::into_raw(Box::new(builder.retract_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/ref`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_retract_ref<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::Ref(value);
+    Box::into_raw(Box::new(builder.retract_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/keyword`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_retract_keyword<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: *const c_char) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = kw_from_string(c_char_to_string(value)).into();
+    Box::into_raw(Box::new(builder.retract_kw(&kw, value).into()))
+}
+
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/boolean`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_retract_boolean<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: bool) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.retract_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/double`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_retract_double<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: f64) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.retract_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/instant`.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_retract_timestamp<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: c_longlong) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value: TypedValue = TypedValue::instant(value);
+    Box::into_raw(Box::new(builder.retract_kw(&kw, value).into()))
+}
+
+/// Uses `builder` to retract `value` for `kw` on entity `entid`.
+///
+/// # Errors
+///
+/// If `entid` is not present in the store.
+/// If `kw` is not a valid attribute in the store.
+/// If the type of `kw` is not `:db.type/uuid`.
+///
+/// TODO don't panic if the UUID is not valid - return result instead.
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_retract_uuid<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>, kw: *const c_char, value: *mut [u8; 16]) -> *mut ExternResult {
+    let builder = &mut*builder;
+    let kw = kw_from_string(c_char_to_string(kw));
+    let value = &*value;
+    let value = Uuid::from_bytes(value).expect("valid uuid");
+    let value: TypedValue = value.into();
+    Box::into_raw(Box::new(builder.retract_kw(&kw, value).into()))
+}
+
+/// Transacts all the assertions and retractions that have been performed
+/// using this builder.
+///
+/// This consumes the builder and returns the enclosed [InProgress](mentat::InProgress) transaction
+/// inside the [InProgressTransactResult][::InProgressTransactResult] alongside the [TxReport](mentat::TxReport) generated
+/// by the transact.
+///
+/// # Safety
+///
+/// Callers are responsible for managing the memory for the return value.
+/// The destructors `in_progress_destroy` and `tx_report_destroy` are provided for
+/// releasing the memory for these pointer types.
+///
+/// TODO: Document the errors that can result from transact
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_transact<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>) -> *mut InProgressTransactResult<'a, 'c> {
+    let builder = Box::from_raw(builder);
+    let (in_progress, tx_report) = builder.transact();
+    let result = InProgressTransactResult { in_progress: Box::into_raw(Box::new(in_progress)), result: Box::into_raw(Box::new(tx_report.into())) };
+    Box::into_raw(Box::new(result))
+}
+
+/// Transacts and commits all the assertions and retractions that have been performed
+/// using this builder.
+///
+/// This consumes the builder and the enclosed [InProgress](mentat::InProgress) transaction.
+///
+/// Returns as [Result](std::result::Result) as an [ExternResult](::ExternResult).
+///
+/// TODO: Document the errors that can result from transact
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_commit<'a, 'c>(builder: *mut EntityBuilder<InProgressBuilder<'a, 'c>>) -> *mut ExternResult {
+    let builder = Box::from_raw(builder);
+    Box::into_raw(Box::new(builder.commit().into()))
+}
+
+/// Performs a single transaction against the store.
+///
+/// Returns as [TxReport](mentat::TxReport) as an [ExternResult](::ExternResult).
+/// TODO: Document the errors that can result from transact
 #[no_mangle]
 pub unsafe extern "C" fn store_transact(store: *mut Store, transaction: *const c_char) -> *mut ExternResult {
     let store = &mut*store;
@@ -271,7 +1000,7 @@ pub unsafe extern "C" fn store_transact(store: *mut Store, transaction: *const c
     Box::into_raw(Box::new(result.into()))
 }
 
-/// Fetches the `tx_id` for the given [TxReport](mentat::TxReport).
+/// Fetches the `tx_id` for the given [TxReport](mentat::TxReport)`.
 #[no_mangle]
 pub unsafe extern "C" fn tx_report_get_entid(tx_report: *mut TxReport) -> c_longlong {
     let tx_report = &*tx_report;
@@ -298,9 +1027,40 @@ pub unsafe extern "C" fn tx_report_entity_for_temp_id(tx_report: *mut TxReport,
     }
 }
 
-// TODO: cache
+/// Adds an attribute to the cache.
+/// `store_cache_attribute_forward` caches values for an attribute keyed by entity
+/// (i.e. find values and entities that have this attribute, or find values of attribute for an entity)
+#[no_mangle]
+pub extern "C" fn store_cache_attribute_forward(store: *mut Store, attribute: *const c_char) -> *mut ExternResult {
+    let store = unsafe { &mut *store };
+    let kw = kw_from_string(c_char_to_string(attribute));
+    Box::into_raw(Box::new(store.cache(&kw, CacheDirection::Forward).into()))
+}
 
-// TODO: q_once
+/// Adds an attribute to the cache.
+/// `store_cache_attribute_reverse` caches entities for an attribute keyed by value.
+/// (i.e. find entities that have a particular value for an attribute).
+#[no_mangle]
+pub extern "C" fn store_cache_attribute_reverse(store: *mut Store, attribute: *const c_char) -> *mut ExternResult {
+    let store = unsafe { &mut *store };
+    let kw = kw_from_string(c_char_to_string(attribute));
+    Box::into_raw(Box::new(store.cache(&kw, CacheDirection::Reverse).into()))
+}
+
+/// Adds an attribute to the cache.
+/// `store_cache_attribute_bi_directional` caches entity in both available directions, forward and reverse.
+///
+/// `Forward` caches values for an attribute keyed by entity
+/// (i.e. find values and entities that have this attribute, or find values of attribute for an entity)
+///
+/// `Reverse` caches entities for an attribute keyed by value.
+/// (i.e. find entities that have a particular value for an attribute).
+#[no_mangle]
+pub extern "C" fn store_cache_attribute_bi_directional(store: *mut Store, attribute: *const c_char) -> *mut ExternResult {
+    let store = unsafe { &mut *store };
+    let kw = kw_from_string(c_char_to_string(attribute));
+    Box::into_raw(Box::new(store.cache(&kw, CacheDirection::Both).into()))
+}
 
 /// Creates a [QueryBuilder](mentat::QueryBuilder) from the given store to execute the provided query.
 ///
@@ -510,10 +1270,11 @@ pub unsafe extern "C" fn typed_value_into_long(typed_value: *mut Binding) -> c_l
 ///
 /// # Panics
 ///
-/// If the [ValueType](mentat::ValueType) of the [Binding](mentat::Binding) is not [ValueType::Long](mentat::ValueType::Ref).
+/// If the [ValueType](mentat::ValueType) of the [Binding](mentat::Binding) is not [ValueType::Ref](mentat::ValueType::Ref).
 #[no_mangle]
 pub unsafe extern "C" fn typed_value_into_entid(typed_value: *mut Binding) ->  Entid {
     let typed_value = Box::from_raw(typed_value);
+    println!("typed value as entid {:?}", typed_value);
     unwrap_conversion(typed_value.into_entid(), ValueType::Ref)
 }
 
@@ -521,7 +1282,7 @@ pub unsafe extern "C" fn typed_value_into_entid(typed_value: *mut Binding) -> En
 ///
 /// # Panics
 ///
-/// If the [ValueType](mentat::ValueType) of the [Binding](mentat::Binding) is not [ValueType::Long](mentat::ValueType::Ref).
+/// If the [ValueType](mentat::ValueType) of the [Binding](mentat::Binding) is not [ValueType::Ref](mentat::ValueType::Ref).
 #[no_mangle]
 pub unsafe extern "C" fn typed_value_into_kw(typed_value: *mut Binding) ->  *const c_char {
     let typed_value = Box::from_raw(typed_value);
@@ -607,7 +1368,7 @@ pub unsafe extern "C" fn row_at_index(rows: *mut RelResult<Binding>, index: c_in
     result.row(index as usize).map_or_else(std::ptr::null_mut, |v| Box::into_raw(Box::new(v.to_vec())))
 }
 
-/// Consumes the `Vec<Vec<Binding>>` and returns an iterator over the values.
+/// Consumes the `RelResult<Binding>` and returns an iterator over the values.
 ///
 /// # Safety
 ///
@@ -905,6 +1666,18 @@ pub unsafe extern "C" fn changelist_entry_at(tx_report: *mut TransactionChange,
     tx_report.changes[index].clone()
 }
 
+/// Destructor for releasing the memory of [InProgressBuilder](mentat::InProgressBuilder).
+#[no_mangle]
+pub unsafe extern "C" fn in_progress_builder_destroy<'a, 'c>(obj: *mut InProgressBuilder<'a, 'c>) {
+    let _ = Box::from_raw(obj);
+}
+
+/// Destructor for releasing the memory of [EntityBuilder](mentat::EntityBuilder).
+#[no_mangle]
+pub unsafe extern "C" fn entity_builder_destroy<'a, 'c>(obj: *mut EntityBuilder<InProgressBuilder<'a, 'c>>) {
+    let _ = Box::from_raw(obj);
+}
+
 /// destroy function for releasing the memory for `repr(C)` structs.
 #[no_mangle]
 pub unsafe extern "C" fn destroy(obj: *mut c_void) {
@@ -933,12 +1706,17 @@ define_destructor!(tx_report_destroy, TxReport);
 /// Destructor for releasing the memory of [Binding](mentat::Binding).
 define_destructor!(typed_value_destroy, Binding);
 
+/// Destructor for releasing the memory of [Vec<Binding>][mentat::Binding].
 define_destructor!(typed_value_list_destroy, Vec<Binding>);
 
 /// Destructor for releasing the memory of [BindingIterator](BindingIterator) .
 define_destructor!(typed_value_list_iter_destroy, BindingIterator);
 
+/// Destructor for releasing the memory of [RelResult<Binding>](mentat::RelResult).
 define_destructor!(typed_value_result_set_destroy, RelResult<Binding>);
 
-/// Destructor for releasing the memory of [BindingListIterator](BindingListIterator) .
+/// Destructor for releasing the memory of [BindingListIterator](::BindingListIterator).
 define_destructor!(typed_value_result_set_iter_destroy, BindingListIterator);
+
+/// Destructor for releasing the memory of [InProgress](mentat::InProgress).
+define_destructor!(in_progress_destroy, InProgress);

sdks/android/Mentat/library/src/androidTest/java/com/mozilla/mentat/FFIIntegrationTest.java

@@ -14,6 +14,7 @@ import android.content.Context;
 import android.content.res.AssetManager;
 import android.support.test.InstrumentationRegistry;
 import android.support.test.runner.AndroidJUnit4;
+import android.util.Log;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -22,7 +23,6 @@ import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
-import java.nio.ByteBuffer;
 import java.text.DateFormat;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
@@ -40,6 +40,33 @@ import static org.junit.Assert.*;
 @RunWith(AndroidJUnit4.class)
 public class FFIIntegrationTest {
 
+    class DBSetupResult {
+        TxReport schemaReport;
+        TxReport dataReport;
+
+        public DBSetupResult(TxReport schemaReport, TxReport dataReport) {
+            this.schemaReport = schemaReport;
+            this.dataReport = dataReport;
+        }
+    }
+
+    class QueryTimer {
+        private long startTime = 0;
+        private long endTime = 0;
+
+        public void start() {
+            this.startTime = System.nanoTime();
+        }
+
+        public void end() {
+            this.endTime = System.nanoTime();
+        }
+
+        public long duration() {
+            return this.endTime - this.startTime;
+        }
+    }
+
     Mentat mentat = null;
 
     @Test
@@ -95,7 +122,8 @@ public class FFIIntegrationTest {
         return this.mentat;
     }
 
-    public TxReport populateWithTypesSchema(Mentat mentat) {
+    public DBSetupResult populateWithTypesSchema(Mentat mentat) {
+        InProgress transaction = mentat.beginTransaction();
         String schema = "[\n" +
                 "                [:db/add \"b\" :db/ident :foo/boolean]\n" +
                 "                [:db/add \"b\" :db/valueType :db.type/boolean]\n" +
@@ -122,7 +150,7 @@ public class FFIIntegrationTest {
                 "                [:db/add \"u\" :db/valueType :db.type/uuid]\n" +
                 "                [:db/add \"u\" :db/cardinality :db.cardinality/one]\n" +
                 "            ]";
-        TxReport report = mentat.transact(schema);
+        TxReport report = transaction.transact(schema);
         Long stringEntid = report.getEntidForTempId("s");
 
         String data = "[\n" +
@@ -135,13 +163,16 @@ public class FFIIntegrationTest {
                 "                [:db/add \"a\" :foo/uuid #uuid \"550e8400-e29b-41d4-a716-446655440000\"]\n" +
                 "                [:db/add \"b\" :foo/boolean false]\n" +
                 "                [:db/add \"b\" :foo/ref "+ stringEntid +"]\n" +
+                "                [:db/add \"b\" :foo/keyword :foo/string]\n" +
                 "                [:db/add \"b\" :foo/long 50]\n" +
                 "                [:db/add \"b\" :foo/instant #inst \"2018-01-01T11:00:00.000Z\"]\n" +
                 "                [:db/add \"b\" :foo/double 22.46]\n" +
                 "                [:db/add \"b\" :foo/string \"Silence is worse; all truths that are kept silent become poisonous.\"]\n" +
                 "                [:db/add \"b\" :foo/uuid #uuid \"4cb3f828-752d-497a-90c9-b1fd516d5644\"]\n" +
                 "            ]";
-        return mentat.transact(data);
+        TxReport dataReport = transaction.transact(data);
+        transaction.commit();
+        return new DBSetupResult(report, dataReport);
     }
 
     @Test
@@ -168,7 +199,7 @@ public class FFIIntegrationTest {
         Mentat mentat = openAndInitializeCitiesStore();
         String query = "[:find ?n . :in ?name :where [(fulltext $ :community/name ?name) [[?e ?n]]]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindString("?name", "Wallingford").runScalar(new ScalarResultHandler() {
+        mentat.query(query).bind("?name", "Wallingford").run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -187,7 +218,7 @@ public class FFIIntegrationTest {
         Mentat mentat = openAndInitializeCitiesStore();
         String query = "[:find [?when ...] :where [_ :db/txInstant ?when] :order (asc ?when)]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).runColl(new CollResultHandler() {
+        mentat.query(query).run(new CollResultHandler() {
             @Override
             public void handleList(CollResult list) {
                 assertNotNull(list);
@@ -208,7 +239,7 @@ public class FFIIntegrationTest {
         Mentat mentat = openAndInitializeCitiesStore();
         String query = "[:find [?when ...] :where [_ :db/txInstant ?when] :order (asc ?when)]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).runColl(new CollResultHandler() {
+        mentat.query(query).run(new CollResultHandler() {
             @Override
             public void handleList(CollResult list) {
                 assertNotNull(list);
@@ -234,7 +265,7 @@ public class FFIIntegrationTest {
                 "        [?c :community/type :community.type/website]\n" +
                 "        [(fulltext $ :community/category \"food\") [[?c ?cat]]]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).runTuple(new TupleResultHandler() {
+        mentat.query(query).run(new TupleResultHandler() {
             @Override
             public void handleRow(TupleResult row) {
                 assertNotNull(row);
@@ -333,11 +364,11 @@ public class FFIIntegrationTest {
     @Test
     public void bindingLongValueSucceeds() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?e . :in ?long :where [?e :foo/long ?long]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindLong("?long", 25).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bind("?long", 25).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -354,12 +385,12 @@ public class FFIIntegrationTest {
     @Test
     public void bindingRefValueSucceeds() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         long stringEntid = mentat.entIdForAttribute(":foo/string");
         final Long bEntid = report.getEntidForTempId("b");
         String query = "[:find ?e . :in ?ref :where [?e :foo/ref ?ref]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindEntidReference("?ref", stringEntid).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bindEntidReference("?ref", stringEntid).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -376,12 +407,12 @@ public class FFIIntegrationTest {
     @Test
     public void bindingRefKwValueSucceeds() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         String refKeyword = ":foo/string";
         final Long bEntid = report.getEntidForTempId("b");
         String query = "[:find ?e . :in ?ref :where [?e :foo/ref ?ref]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindKeywordReference("?ref", refKeyword).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bindKeywordReference("?ref", refKeyword).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -398,11 +429,11 @@ public class FFIIntegrationTest {
     @Test
     public void bindingKwValueSucceeds() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?e . :in ?kw :where [?e :foo/keyword ?kw]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindKeyword("?kw", ":foo/string").runScalar(new ScalarResultHandler() {
+        mentat.query(query).bindKeyword("?kw", ":foo/string").run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -419,13 +450,13 @@ public class FFIIntegrationTest {
     @Test
     public void bindingDateValueSucceeds() throws InterruptedException, ParseException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
 
         Date date = new Date(1523896758000L);
         String query = "[:find [?e ?d] :in ?now :where [?e :foo/instant ?d] [(< ?d ?now)]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindDate("?now", date).runTuple(new TupleResultHandler() {
+        mentat.query(query).bind("?now", date).run(new TupleResultHandler() {
             @Override
             public void handleRow(TupleResult row) {
                 assertNotNull(row);
@@ -446,7 +477,7 @@ public class FFIIntegrationTest {
         Mentat mentat = this.openAndInitializeCitiesStore();
         String query = "[:find ?n . :in ?name :where [(fulltext $ :community/name ?name) [[?e ?n]]]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindString("?name", "Wallingford").runScalar(new ScalarResultHandler() {
+        mentat.query(query).bind("?name", "Wallingford").run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -463,12 +494,12 @@ public class FFIIntegrationTest {
     @Test
     public void bindingUuidValueSucceeds() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?e . :in ?uuid :where [?e :foo/uuid ?uuid]]";
         UUID uuid = UUID.fromString("550e8400-e29b-41d4-a716-446655440000");
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindUUID("?uuid", uuid).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bind("?uuid", uuid).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -485,11 +516,11 @@ public class FFIIntegrationTest {
     @Test
     public void bindingBooleanValueSucceeds() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?e . :in ?bool :where [?e :foo/boolean ?bool]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindBoolean("?bool", true).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bind("?bool", true).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -507,11 +538,11 @@ public class FFIIntegrationTest {
     @Test
     public void bindingDoubleValueSucceeds() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?e . :in ?double :where [?e :foo/double ?double]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindDouble("?double", 11.23).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bind("?double", 11.23).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -528,11 +559,11 @@ public class FFIIntegrationTest {
     @Test
     public void typedValueConvertsToLong() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?v . :in ?e :where [?e :foo/long ?v]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindEntidReference("?e", aEntid).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bindEntidReference("?e", aEntid).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -550,11 +581,11 @@ public class FFIIntegrationTest {
     @Test
     public void typedValueConvertsToRef() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?e . :where [?e :foo/long 25]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).runScalar(new ScalarResultHandler() {
+        mentat.query(query).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -572,11 +603,11 @@ public class FFIIntegrationTest {
     @Test
     public void typedValueConvertsToKeyword() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?v . :in ?e :where [?e :foo/keyword ?v]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindEntidReference("?e", aEntid).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bindEntidReference("?e", aEntid).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -594,11 +625,11 @@ public class FFIIntegrationTest {
     @Test
     public void typedValueConvertsToBoolean() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?v . :in ?e :where [?e :foo/boolean ?v]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindEntidReference("?e", aEntid).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bindEntidReference("?e", aEntid).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -616,11 +647,11 @@ public class FFIIntegrationTest {
     @Test
     public void typedValueConvertsToDouble() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?v . :in ?e :where [?e :foo/double ?v]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindEntidReference("?e", aEntid).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bindEntidReference("?e", aEntid).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -638,14 +669,14 @@ public class FFIIntegrationTest {
     @Test
     public void typedValueConvertsToDate() throws InterruptedException, ParseException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?v . :in ?e :where [?e :foo/instant ?v]]";
         final Expectation expectation = new Expectation();
         DateFormat format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZZZZZ", Locale.ENGLISH);
         format.parse("2017-01-01T11:00:00+00:00");
         final Calendar expectedDate = format.getCalendar();
-        mentat.query(query).bindEntidReference("?e", aEntid).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bindEntidReference("?e", aEntid).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -663,11 +694,11 @@ public class FFIIntegrationTest {
     @Test
     public void typedValueConvertsToString() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?v . :in ?e :where [?e :foo/string ?v]]";
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindEntidReference("?e", aEntid).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bindEntidReference("?e", aEntid).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -685,12 +716,12 @@ public class FFIIntegrationTest {
     @Test
     public void typedValueConvertsToUUID() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         String query = "[:find ?v . :in ?e :where [?e :foo/uuid ?v]]";
         final UUID expectedUUID = UUID.fromString("550e8400-e29b-41d4-a716-446655440000");
         final Expectation expectation = new Expectation();
-        mentat.query(query).bindEntidReference("?e", aEntid).runScalar(new ScalarResultHandler() {
+        mentat.query(query).bindEntidReference("?e", aEntid).run(new ScalarResultHandler() {
             @Override
             public void handleValue(TypedValue value) {
                 assertNotNull(value);
@@ -708,7 +739,7 @@ public class FFIIntegrationTest {
     @Test
     public void valueForAttributeOfEntitySucceeds() throws InterruptedException {
         Mentat mentat = new Mentat();
-        TxReport report = this.populateWithTypesSchema(mentat);
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
         final Long aEntid = report.getEntidForTempId("a");
         TypedValue value = mentat.valueForAttributeOfEntity(":foo/long", aEntid);
         assertNotNull(value);
@@ -722,4 +753,569 @@ public class FFIIntegrationTest {
         long entid = mentat.entIdForAttribute(":foo/long");
         assertEquals(65540, entid);
     }
+
+    @Test
+    public void testInProgressTransact() {
+        Mentat mentat = new Mentat();
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
+        assertNotNull(report);
+
+    }
+
+    @Test
+    public void testInProgressRollback() {
+        Mentat mentat = new Mentat();
+        TxReport report = this.populateWithTypesSchema(mentat).dataReport;
+        assertNotNull(report);
+        long aEntid = report.getEntidForTempId("a");
+        TypedValue preLongValue = mentat.valueForAttributeOfEntity(":foo/long", aEntid);
+        assertEquals(25, preLongValue.asLong().longValue());
+
+        InProgress inProgress = mentat.beginTransaction();
+        report = inProgress.transact("[[:db/add "+ aEntid +" :foo/long 22]]");
+        assertNotNull(report);
+        inProgress.rollback();
+
+        TypedValue postLongValue = mentat.valueForAttributeOfEntity(":foo/long", aEntid);
+        assertEquals(25, postLongValue.asLong().longValue());
+    }
+
+    @Test
+    public void testInProgressEntityBuilder() throws InterruptedException {
+        Mentat mentat = new Mentat();
+        DBSetupResult reports = this.populateWithTypesSchema(mentat);
+        long bEntid = reports.dataReport.getEntidForTempId("b");
+        final long longEntid = reports.schemaReport.getEntidForTempId("l");
+        final long stringEntid = reports.schemaReport.getEntidForTempId("s");
+
+        // test that the values are as expected
+        String query = "[:find [?b ?i ?u ?l ?d ?s ?k ?r]\n" +
+                "                     :in ?e\n" +
+                "                :where [?e :foo/boolean ?b]\n" +
+                "                            [?e :foo/instant ?i]\n" +
+                "                            [?e :foo/uuid ?u]\n" +
+                "                            [?e :foo/long ?l]\n" +
+                "                            [?e :foo/double ?d]\n" +
+                "                            [?e :foo/string ?s]\n" +
+                "                            [?e :foo/keyword ?k]\n" +
+                "                            [?e :foo/ref ?r]]";
+
+        final Expectation expectation1 = new Expectation();
+        mentat.query(query).bindEntidReference("?e", bEntid).run(new TupleResultHandler() {
+            @Override
+            public void handleRow(TupleResult row) {
+                assertNotNull(row);
+                assertEquals(false, row.asBool(0));
+                assertEquals(new Date(1514804400000l), row.asDate(1));
+                assertEquals(UUID.fromString("4cb3f828-752d-497a-90c9-b1fd516d5644"), row.asUUID(2));
+                assertEquals(50, row.asLong(3).longValue());
+                assertEquals(new Double(22.46), row.asDouble(4));
+                assertEquals("Silence is worse; all truths that are kept silent become poisonous.", row.asString(5));
+                assertEquals(":foo/string", row.asKeyword(6));
+                assertEquals(stringEntid, row.asEntid(7).longValue());
+                expectation1.fulfill();
+            }
+        });
+
+        synchronized (expectation1) {
+            expectation1.wait(1000);
+        }
+        assertTrue(expectation1.isFulfilled);
+
+        InProgressBuilder builder = mentat.entityBuilder();
+        builder.add(bEntid, ":foo/boolean", true);
+        final Date newDate = new Date(1524743301000l);
+        builder.add(bEntid, ":foo/instant", newDate);
+        final UUID newUUID = UUID.randomUUID();
+        builder.add(bEntid, ":foo/uuid", newUUID);
+        builder.add(bEntid, ":foo/long", 75);
+        builder.add(bEntid, ":foo/double", 81.3);
+        builder.add(bEntid, ":foo/string", "Become who you are!");
+        builder.addKeyword(bEntid, ":foo/keyword", ":foo/long");
+        builder.addRef(bEntid, ":foo/ref", longEntid);
+        builder.commit();
+
+
+        final Expectation expectation2 = new Expectation();
+        mentat.query(query).bindEntidReference("?e", bEntid).run(new TupleResultHandler() {
+            @Override
+            public void handleRow(TupleResult row) {
+                assertNotNull(row);
+                assertEquals(true, row.asBool(0));
+                System.out.println(row.asDate(1).getTime());
+                assertEquals(newDate, row.asDate(1));
+                assertEquals(newUUID, row.asUUID(2));
+                assertEquals(75, row.asLong(3).longValue());
+                assertEquals(new Double(81.3), row.asDouble(4));
+                assertEquals("Become who you are!", row.asString(5));
+                assertEquals(":foo/long", row.asKeyword(6));
+                assertEquals(longEntid, row.asEntid(7).longValue());
+                expectation2.fulfill();
+            }
+        });
+
+        synchronized (expectation2) {
+            expectation2.wait(1000);
+        }
+        assertTrue(expectation2.isFulfilled);
+    }
+
+    @Test
+    public void testEntityBuilderForEntid() throws InterruptedException {
+        Mentat mentat = new Mentat();
+        DBSetupResult reports = this.populateWithTypesSchema(mentat);
+        long bEntid = reports.dataReport.getEntidForTempId("b");
+        final long longEntid = reports.schemaReport.getEntidForTempId("l");
+        final long stringEntid = reports.schemaReport.getEntidForTempId("s");
+
+        // test that the values are as expected
+        String query = "[:find [?b ?i ?u ?l ?d ?s ?k ?r]\n" +
+                "                     :in ?e\n" +
+                "                :where [?e :foo/boolean ?b]\n" +
+                "                            [?e :foo/instant ?i]\n" +
+                "                            [?e :foo/uuid ?u]\n" +
+                "                            [?e :foo/long ?l]\n" +
+                "                            [?e :foo/double ?d]\n" +
+                "                            [?e :foo/string ?s]\n" +
+                "                            [?e :foo/keyword ?k]\n" +
+                "                            [?e :foo/ref ?r]]";
+
+        final Expectation expectation1 = new Expectation();
+        mentat.query(query).bindEntidReference("?e", bEntid).run(new TupleResultHandler() {
+            @Override
+            public void handleRow(TupleResult row) {
+                assertNotNull(row);
+                assertEquals(false, row.asBool(0));
+                assertEquals(new Date(1514804400000l), row.asDate(1));
+                assertEquals(UUID.fromString("4cb3f828-752d-497a-90c9-b1fd516d5644"), row.asUUID(2));
+                assertEquals(50, row.asLong(3).longValue());
+                assertEquals(new Double(22.46), row.asDouble(4));
+                assertEquals("Silence is worse; all truths that are kept silent become poisonous.", row.asString(5));
+                assertEquals(":foo/string", row.asKeyword(6));
+                assertEquals(stringEntid, row.asEntid(7).longValue());
+                expectation1.fulfill();
+            }
+        });
+
+        synchronized (expectation1) {
+            expectation1.wait(1000);
+        }
+        assertTrue(expectation1.isFulfilled);
+
+        EntityBuilder builder = mentat.entityBuilder(bEntid);
+        builder.add(":foo/boolean", true);
+        final Date newDate = new Date(1524743301000l);
+        builder.add(":foo/instant", newDate);
+        final UUID newUUID = UUID.randomUUID();
+        builder.add(":foo/uuid", newUUID);
+        builder.add(":foo/long", 75);
+        builder.add(":foo/double", 81.3);
+        builder.add(":foo/string", "Become who you are!");
+        builder.addKeyword(":foo/keyword", ":foo/long");
+        builder.addRef(":foo/ref", longEntid);
+        builder.commit();
+
+
+        final Expectation expectation2 = new Expectation();
+        mentat.query(query).bindEntidReference("?e", bEntid).run(new TupleResultHandler() {
+            @Override
+            public void handleRow(TupleResult row) {
+                assertNotNull(row);
+                assertEquals(true, row.asBool(0));
+                System.out.println(row.asDate(1).getTime());
+                assertEquals(newDate, row.asDate(1));
+                assertEquals(newUUID, row.asUUID(2));
+                assertEquals(75, row.asLong(3).longValue());
+                assertEquals(new Double(81.3), row.asDouble(4));
+                assertEquals("Become who you are!", row.asString(5));
+                assertEquals(":foo/long", row.asKeyword(6));
+                assertEquals(longEntid, row.asEntid(7).longValue());
+                expectation2.fulfill();
+            }
+        });
+
+        synchronized (expectation2) {
+            expectation2.wait(1000);
+        }
+        assertTrue(expectation2.isFulfilled);
+    }
+
+    @Test
+    public void testEntityBuilderForTempid() throws InterruptedException {
+        Mentat mentat = new Mentat();
+        DBSetupResult reports = this.populateWithTypesSchema(mentat);
+        final long longEntid = reports.schemaReport.getEntidForTempId("l");
+
+        EntityBuilder builder = mentat.entityBuilder("c");
+        builder.add(":foo/boolean", true);
+        final Date newDate = new Date(1524743301000l);
+        builder.add(":foo/instant", newDate);
+        final UUID newUUID = UUID.randomUUID();
+        builder.add(":foo/uuid", newUUID);
+        builder.add(":foo/long", 75);
+        builder.add(":foo/double", 81.3);
+        builder.add(":foo/string", "Become who you are!");
+        builder.addKeyword(":foo/keyword", ":foo/long");
+        builder.addRef(":foo/ref", longEntid);
+        TxReport report = builder.commit();
+        long cEntid = report.getEntidForTempId("c");
+
+        // test that the values are as expected
+        String query = "[:find [?b ?i ?u ?l ?d ?s ?k ?r]\n" +
+                "                     :in ?e\n" +
+                "                :where [?e :foo/boolean ?b]\n" +
+                "                            [?e :foo/instant ?i]\n" +
+                "                            [?e :foo/uuid ?u]\n" +
+                "                            [?e :foo/long ?l]\n" +
+                "                            [?e :foo/double ?d]\n" +
+                "                            [?e :foo/string ?s]\n" +
+                "                            [?e :foo/keyword ?k]\n" +
+                "                            [?e :foo/ref ?r]]";
+
+        final Expectation expectation = new Expectation();
+        mentat.query(query).bindEntidReference("?e", cEntid).run(new TupleResultHandler() {
+            @Override
+            public void handleRow(TupleResult row) {
+                assertNotNull(row);
+                assertEquals(true, row.asBool(0));
+                System.out.println(row.asDate(1).getTime());
+                assertEquals(newDate, row.asDate(1));
+                assertEquals(newUUID, row.asUUID(2));
+                assertEquals(75, row.asLong(3).longValue());
+                assertEquals(new Double(81.3), row.asDouble(4));
+                assertEquals("Become who you are!", row.asString(5));
+                assertEquals(":foo/long", row.asKeyword(6));
+                assertEquals(longEntid, row.asEntid(7).longValue());
+                expectation.fulfill();
+            }
+        });
+
+        synchronized (expectation) {
+            expectation.wait(1000);
+        }
+        assertTrue(expectation.isFulfilled);
+    }
+
+    @Test
+    public void testInProgressBuilderTransact() throws InterruptedException {
+        Mentat mentat = new Mentat();
+        DBSetupResult reports = this.populateWithTypesSchema(mentat);
+        long aEntid = reports.dataReport.getEntidForTempId("a");
+        long bEntid = reports.dataReport.getEntidForTempId("b");
+        final long longEntid = reports.schemaReport.getEntidForTempId("l");
+        InProgressBuilder builder = mentat.entityBuilder();
+        builder.add(bEntid, ":foo/boolean", true);
+        final Date newDate = new Date(1524743301000l);
+        builder.add(bEntid, ":foo/instant", newDate);
+        final UUID newUUID = UUID.randomUUID();
+        builder.add(bEntid, ":foo/uuid", newUUID);
+        builder.add(bEntid, ":foo/long", 75);
+        builder.add(bEntid, ":foo/double", 81.3);
+        builder.add(bEntid, ":foo/string", "Become who you are!");
+        builder.addKeyword(bEntid, ":foo/keyword", ":foo/long");
+        builder.addRef(bEntid, ":foo/ref", longEntid);
+        InProgressTransactionResult result = builder.transact();
+        assertNotNull(result);
+        assertNotNull(result.getInProgress());
+        assertNotNull(result.getReport());
+        result.getInProgress().transact("[[:db/add "+ aEntid +" :foo/long 22]]");
+        result.getInProgress().commit();
+
+        // test that the values are as expected
+        String query = "[:find [?b ?i ?u ?l ?d ?s ?k ?r]\n" +
+                "                     :in ?e\n" +
+                "                :where [?e :foo/boolean ?b]\n" +
+                "                            [?e :foo/instant ?i]\n" +
+                "                            [?e :foo/uuid ?u]\n" +
+                "                            [?e :foo/long ?l]\n" +
+                "                            [?e :foo/double ?d]\n" +
+                "                            [?e :foo/string ?s]\n" +
+                "                            [?e :foo/keyword ?k]\n" +
+                "                            [?e :foo/ref ?r]]";
+
+        final Expectation expectation = new Expectation();
+        mentat.query(query).bindEntidReference("?e", bEntid).run(new TupleResultHandler() {
+            @Override
+            public void handleRow(TupleResult row) {
+                assertNotNull(row);
+                assertEquals(true, row.asBool(0));
+                System.out.println(row.asDate(1).getTime());
+                assertEquals(newDate, row.asDate(1));
+                assertEquals(newUUID, row.asUUID(2));
+                assertEquals(75, row.asLong(3).longValue());
+                assertEquals(new Double(81.3), row.asDouble(4));
+                assertEquals("Become who you are!", row.asString(5));
+                assertEquals(":foo/long", row.asKeyword(6));
+                assertEquals(longEntid, row.asEntid(7).longValue());
+                expectation.fulfill();
+            }
+        });
+
+        synchronized (expectation) {
+            expectation.wait(1000);
+        }
+        assertTrue(expectation.isFulfilled);
+
+        TypedValue longValue = mentat.valueForAttributeOfEntity(":foo/long", aEntid);
+        assertEquals(22, longValue.asLong().longValue());
+    }
+
+    @Test
+    public void testEntityBuilderTransact() throws InterruptedException {
+        Mentat mentat = new Mentat();
+        DBSetupResult reports = this.populateWithTypesSchema(mentat);
+        long aEntid = reports.dataReport.getEntidForTempId("a");
+        long bEntid = reports.dataReport.getEntidForTempId("b");
+        final long longEntid = reports.schemaReport.getEntidForTempId("l");
+
+        EntityBuilder builder = mentat.entityBuilder(bEntid);
+        builder.add(":foo/boolean", true);
+        final Date newDate = new Date(1524743301000l);
+        builder.add(":foo/instant", newDate);
+        final UUID newUUID = UUID.randomUUID();
+        builder.add(":foo/uuid", newUUID);
+        builder.add(":foo/long", 75);
+        builder.add(":foo/double", 81.3);
+        builder.add(":foo/string", "Become who you are!");
+        builder.addKeyword(":foo/keyword", ":foo/long");
+        builder.addRef(":foo/ref", longEntid);
+        InProgressTransactionResult result = builder.transact();
+        assertNotNull(result);
+        assertNotNull(result.getInProgress());
+        assertNotNull(result.getReport());
+        result.getInProgress().transact("[[:db/add "+ aEntid +" :foo/long 22]]");
+        result.getInProgress().commit();
+
+        // test that the values are as expected
+        String query = "[:find [?b ?i ?u ?l ?d ?s ?k ?r]\n" +
+                "                     :in ?e\n" +
+                "                :where [?e :foo/boolean ?b]\n" +
+                "                            [?e :foo/instant ?i]\n" +
+                "                            [?e :foo/uuid ?u]\n" +
+                "                            [?e :foo/long ?l]\n" +
+                "                            [?e :foo/double ?d]\n" +
+                "                            [?e :foo/string ?s]\n" +
+                "                            [?e :foo/keyword ?k]\n" +
+                "                            [?e :foo/ref ?r]]";
+
+        final Expectation expectation = new Expectation();
+        mentat.query(query).bindEntidReference("?e", bEntid).run(new TupleResultHandler() {
+            @Override
+            public void handleRow(TupleResult row) {
+                assertNotNull(row);
+                assertEquals(true, row.asBool(0));
+                System.out.println(row.asDate(1).getTime());
+                assertEquals(newDate, row.asDate(1));
+                assertEquals(newUUID, row.asUUID(2));
+                assertEquals(75, row.asLong(3).longValue());
+                assertEquals(new Double(81.3), row.asDouble(4));
+                assertEquals("Become who you are!", row.asString(5));
+                assertEquals(":foo/long", row.asKeyword(6));
+                assertEquals(longEntid, row.asEntid(7).longValue());
+                expectation.fulfill();
+            }
+        });
+
+        synchronized (expectation) {
+            expectation.wait(1000);
+        }
+        assertTrue(expectation.isFulfilled);
+
+        TypedValue longValue = mentat.valueForAttributeOfEntity(":foo/long", aEntid);
+        assertEquals(22, longValue.asLong().longValue());
+    }
+
+    @Test
+    public void testEntityBuilderRetract() throws InterruptedException {
+        Mentat mentat = new Mentat();
+        DBSetupResult reports = this.populateWithTypesSchema(mentat);
+        long bEntid = reports.dataReport.getEntidForTempId("b");
+        final long longEntid = reports.schemaReport.getEntidForTempId("l");
+        final long stringEntid = reports.schemaReport.getEntidForTempId("s");
+
+        // test that the values are as expected
+        String query = "[:find [?b ?i ?u ?l ?d ?s ?k ?r]\n" +
+                "                     :in ?e\n" +
+                "                :where [?e :foo/boolean ?b]\n" +
+                "                            [?e :foo/instant ?i]\n" +
+                "                            [?e :foo/uuid ?u]\n" +
+                "                            [?e :foo/long ?l]\n" +
+                "                            [?e :foo/double ?d]\n" +
+                "                            [?e :foo/string ?s]\n" +
+                "                            [?e :foo/keyword ?k]\n" +
+                "                            [?e :foo/ref ?r]]";
+
+        final Expectation expectation1 = new Expectation();
+        final Date previousDate = new Date(1514804400000l);
+        final UUID previousUuid = UUID.fromString("4cb3f828-752d-497a-90c9-b1fd516d5644");
+        mentat.query(query).bindEntidReference("?e", bEntid).run(new TupleResultHandler() {
+            @Override
+            public void handleRow(TupleResult row) {
+                assertNotNull(row);
+                assertEquals(false, row.asBool(0));
+                assertEquals(previousDate, row.asDate(1));
+                assertEquals(previousUuid, row.asUUID(2));
+                assertEquals(50, row.asLong(3).longValue());
+                assertEquals(new Double(22.46), row.asDouble(4));
+                assertEquals("Silence is worse; all truths that are kept silent become poisonous.", row.asString(5));
+                assertEquals(":foo/string", row.asKeyword(6));
+                assertEquals(stringEntid, row.asEntid(7).longValue());
+                expectation1.fulfill();
+            }
+        });
+
+        synchronized (expectation1) {
+            expectation1.wait(1000);
+        }
+        assertTrue(expectation1.isFulfilled);
+
+        EntityBuilder builder = mentat.entityBuilder(bEntid);
+        builder.retract(":foo/boolean", false);
+        builder.retract(":foo/instant", previousDate);
+        builder.retract(":foo/uuid", previousUuid);
+        builder.retract(":foo/long", 50);
+        builder.retract(":foo/double", 22.46);
+        builder.retract(":foo/string", "Silence is worse; all truths that are kept silent become poisonous.");
+        builder.retractKeyword(":foo/keyword", ":foo/string");
+        builder.retractRef(":foo/ref", stringEntid);
+        builder.commit();
+
+        final Expectation expectation2 = new Expectation();
+        mentat.query(query).bindEntidReference("?e", bEntid).run(new TupleResultHandler() {
+            @Override
+            public void handleRow(TupleResult row) {
+                assertNull(row);
+                expectation2.fulfill();
+            }
+        });
+
+        synchronized (expectation2) {
+            expectation2.wait(1000);
+        }
+        assertTrue(expectation2.isFulfilled);
+    }
+
+    @Test
+    public void testInProgressBuilderRetract() throws InterruptedException {
+        Mentat mentat = new Mentat();
+        DBSetupResult reports = this.populateWithTypesSchema(mentat);
+        long bEntid = reports.dataReport.getEntidForTempId("b");
+        final long longEntid = reports.schemaReport.getEntidForTempId("l");
+        final long stringEntid = reports.schemaReport.getEntidForTempId("s");
+
+        // test that the values are as expected
+        String query = "[:find [?b ?i ?u ?l ?d ?s ?k ?r]\n" +
+                "                     :in ?e\n" +
+                "                :where [?e :foo/boolean ?b]\n" +
+                "                            [?e :foo/instant ?i]\n" +
+                "                            [?e :foo/uuid ?u]\n" +
+                "                            [?e :foo/long ?l]\n" +
+                "                            [?e :foo/double ?d]\n" +
+                "                            [?e :foo/string ?s]\n" +
+                "                            [?e :foo/keyword ?k]\n" +
+                "                            [?e :foo/ref ?r]]";
+
+        final Expectation expectation1 = new Expectation();
+        final Date previousDate = new Date(1514804400000l);
+        final UUID previousUuid = UUID.fromString("4cb3f828-752d-497a-90c9-b1fd516d5644");
+        mentat.query(query).bindEntidReference("?e", bEntid).run(new TupleResultHandler() {
+            @Override
+            public void handleRow(TupleResult row) {
+                assertNotNull(row);
+                assertEquals(false, row.asBool(0));
+                assertEquals(previousDate, row.asDate(1));
+                assertEquals(previousUuid, row.asUUID(2));
+                assertEquals(50, row.asLong(3).longValue());
+                assertEquals(new Double(22.46), row.asDouble(4));
+                assertEquals("Silence is worse; all truths that are kept silent become poisonous.", row.asString(5));
+                assertEquals(":foo/string", row.asKeyword(6));
+                assertEquals(stringEntid, row.asEntid(7).longValue());
+                expectation1.fulfill();
+            }
+        });
+
+        synchronized (expectation1) {
+            expectation1.wait(1000);
+        }
+        assertTrue(expectation1.isFulfilled);
+
+        InProgressBuilder builder = mentat.entityBuilder();
+        builder.retract(bEntid, ":foo/boolean", false);
+        builder.retract(bEntid, ":foo/instant", previousDate);
+        builder.retract(bEntid, ":foo/uuid", previousUuid);
+        builder.retract(bEntid, ":foo/long", 50);
+        builder.retract(bEntid, ":foo/double", 22.46);
+        builder.retract(bEntid, ":foo/string", "Silence is worse; all truths that are kept silent become poisonous.");
+        builder.retractKeyword(bEntid, ":foo/keyword", ":foo/string");
+        builder.retractRef(bEntid, ":foo/ref", stringEntid);
+        builder.commit();
+
+        final Expectation expectation2 = new Expectation();
+        mentat.query(query).bindEntidReference("?e", bEntid).run(new TupleResultHandler() {
+            @Override
+            public void handleRow(TupleResult row) {
+                assertNull(row);
+                expectation2.fulfill();
+            }
+        });
+
+        synchronized (expectation2) {
+            expectation2.wait(1000);
+        }
+        assertTrue(expectation2.isFulfilled);
+    }
+
+    @Test
+    public void testCaching() throws InterruptedException {
+        String query = "[:find ?district :where\n" +
+                "    [?neighborhood :neighborhood/name \"Beacon Hill\"]\n" +
+                "    [?neighborhood :neighborhood/district ?d]\n" +
+                "    [?d :district/name ?district]]";
+
+        Mentat mentat = openAndInitializeCitiesStore();
+
+        final Expectation expectation1 = new Expectation();
+        final QueryTimer uncachedTimer = new QueryTimer();
+        uncachedTimer.start();
+        mentat.query(query).run(new RelResultHandler() {
+            @Override
+            public void handleRows(RelResult rows) {
+                uncachedTimer.end();
+                assertNotNull(rows);
+                expectation1.fulfill();
+            }
+        });
+
+        synchronized (expectation1) {
+            expectation1.wait(1000);
+        }
+        assertTrue(expectation1.isFulfilled);
+
+        mentat.cache(":neighborhood/name", CacheDirection.REVERSE);
+        mentat.cache(":neighborhood/district", CacheDirection.FORWARD);
+
+        final Expectation expectation2 = new Expectation();
+        final QueryTimer cachedTimer = new QueryTimer();
+        cachedTimer.start();
+        mentat.query(query).run(new RelResultHandler() {
+            @Override
+            public void handleRows(RelResult rows) {
+                cachedTimer.end();
+                assertNotNull(rows);
+                expectation2.fulfill();
+            }
+        });
+
+        synchronized (expectation2) {
+            expectation2.wait(1000);
+        }
+        assertTrue(expectation2.isFulfilled);
+
+        long timingDifference = uncachedTimer.duration() - cachedTimer.duration();
+        Log.d("testCaching", "Cached query is "+ timingDifference +" nanoseconds faster than the uncached query");
+
+        assert cachedTimer.duration() < uncachedTimer.duration();
+
+    }
+
 }

sdks/android/Mentat/library/src/main/java/com/mozilla/mentat/CacheDirection.java

@@ -0,0 +1,15 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * Copyright 2018 Mozilla
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+ * this file except in compliance with the License. You may obtain a copy of the
+ * License at http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software distributed
+ * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License. */
+
+package com.mozilla.mentat;
+
+public enum CacheDirection {
+    FORWARD, REVERSE, BOTH
+}

sdks/android/Mentat/library/src/main/java/com/mozilla/mentat/EntityBuilder.java

@@ -0,0 +1,357 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * Copyright 2018 Mozilla
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+ * this file except in compliance with the License. You may obtain a copy of the
+ * License at http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software distributed
+ * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License. */
+
+package com.mozilla.mentat;
+
+import android.util.Log;
+
+import com.sun.jna.Memory;
+import com.sun.jna.Pointer;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.Date;
+import java.util.UUID;
+
+/**
+ * This class wraps a raw pointer that points to a Rust `EntityBuilder<InProgressBuilder>` object.
+ *
+ * {@link EntityBuilder} provides a programmatic interface to performing assertions on a specific entity.
+ * It provides functions for adding and retracting values for attributes for an entity within
+ * an in progress transaction.
+ * <p/>
+ * The `transact` function will transact the assertions that have been added to the {@link EntityBuilder}
+ * and pass back the {@link TxReport} that was generated by this transact and the {@link InProgress} that was
+ * used to perform the transact. This enables you to perform further transacts on the same {@link InProgress}
+ * before committing.
+ * <p/>
+ * <pre>{@code
+ * long aEntid = txReport.getEntidForTempId("a");
+ * long bEntid = txReport.getEntidForTempId("b");
+ * EntityBuilder builder = mentat.getEntityBuilderForEntid(bEntid);
+ * builder.add(":foo/boolean", true);
+ * builder.add(":foo/instant", newDate);
+ * InProgress inProgress = builder.transact().getInProgress();
+ * inProgress.transact("[[:db/add \(aEntid) :foo/long 22]]");
+ * inProgress.commit();
+ * }</pre>
+ * <p/>
+ * The `commit` function will transact and commit the assertions that have been added to the {@link EntityBuilder}.
+ * It will consume the {@link InProgress} used to perform the transact. It returns the {@link TxReport} generated by
+ * the transact. After calling `commit`, a new transaction must be started by calling <pre>Mentat.beginTransaction()</pre>
+ * in order to perform further actions.
+ * <p/>
+ * <pre>{@code
+ * long aEntid = txReport.getEntidForTempId("a");
+ * EntityBuilder builder = mentat.getEntityBuilderForEntid(bEntid);
+ * builder.add(":foo/boolean", true);
+ * builder.add(":foo/instant", newDate);
+ * builder.commit();
+ * }</pre>
+ */
+public class EntityBuilder extends RustObject {
+
+    public EntityBuilder(Pointer pointer) {
+        this.rawPointer = pointer;
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(String keyword, long value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_add_long(this.rawPointer, keyword, value);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void addRef(String keyword, long value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_add_ref(this.rawPointer, keyword, value);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void addKeyword(String keyword, String value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_add_keyword(this.rawPointer, keyword, value);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(String keyword, boolean value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_add_boolean(this.rawPointer, keyword, value ? 1 : 0);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(String keyword, double value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_add_double(this.rawPointer, keyword, value);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(String keyword, Date value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_add_timestamp(this.rawPointer, keyword, value.getTime() * 1_000);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(String keyword, String value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_add_string(this.rawPointer, keyword, value);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(String keyword, UUID value) {
+        this.validate();
+
+        RustResult result = JNA.INSTANCE.entity_builder_add_uuid(this.rawPointer, keyword, getPointerForUUID(value));
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(String keyword, long value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_retract_long(this.rawPointer, keyword, value);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retractRef(String keyword, long value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_retract_ref(this.rawPointer, keyword, value);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retractKeyword(String keyword, String value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_retract_keyword(this.rawPointer, keyword, value);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(String keyword, boolean value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_retract_boolean(this.rawPointer, keyword, value ? 1 : 0);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(String keyword, double value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_retract_double(this.rawPointer, keyword, value);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(String keyword, Date value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_retract_timestamp(this.rawPointer, keyword, value.getTime() * 1_000);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(String keyword, String value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_retract_string(this.rawPointer, keyword, value);
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(String keyword, UUID value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_retract_uuid(this.rawPointer, keyword, this.getPointerForUUID(value));
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+        }
+    }
+
+    /**
+     * Transacts the added assertions. This consumes the pointer associated with this {@link EntityBuilder}
+     * such that no further assertions can be added after the `transact` has completed. To perform
+     * further assertions, use the {@link InProgress} inside the {@link InProgressTransactionResult}
+     * returned from this function.
+     * <p/>
+     * This does not commit the transaction. In order to do so, `commit` can be called on the
+     * {@link InProgress} inside the {@link InProgressTransactionResult} returned from this function.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @return A {@link InProgressTransactionResult} containing the current {@link InProgress} and
+     * the {@link TxReport}  generated by the transact.
+     */
+    public InProgressTransactionResult transact() {
+        this.validate();
+        InProgressTransactionResult result = JNA.INSTANCE.entity_builder_transact(this.rawPointer);
+        this.rawPointer = null;
+        return result;
+    }
+
+    /**
+     * Transacts the added assertions and commits. This consumes the pointer associated with this
+     * {@link EntityBuilder} and the associated {@link InProgress} such that no further assertions
+     * can be added after the `commit` has completed.
+     * <p/>
+     * To perform further assertions, a new `{@link InProgress} or {@link EntityBuilder} should be
+     * created.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @return
+     */
+    public TxReport commit() {
+        this.validate();
+        RustResult result = JNA.INSTANCE.entity_builder_commit(this.rawPointer);
+        this.rawPointer = null;
+        if (result.isFailure()) {
+            Log.e("EntityBuilder", result.err);
+            return null;
+        }
+
+        return new TxReport(result.ok);
+    }
+
+    @Override
+    public void close() throws IOException {
+        if (this.rawPointer != null) {
+            JNA.INSTANCE.entity_builder_destroy(this.rawPointer);
+        }
+    }
+}

sdks/android/Mentat/library/src/main/java/com/mozilla/mentat/InProgress.java

@@ -0,0 +1,195 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * Copyright 2018 Mozilla
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+ * this file except in compliance with the License. You may obtain a copy of the
+ * License at http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software distributed
+ * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License. */
+
+package com.mozilla.mentat;
+
+import android.util.Log;
+
+import com.sun.jna.Pointer;
+
+import java.io.IOException;
+
+/**
+ * This class wraps a raw pointer that points to a Rust {@link InProgress} object.
+ * </p>
+ * {@link InProgress} allows for multiple transacts to be performed in a single transaction.
+ * Each transact performed results in a {@link TxReport} that can be used to gather information
+ * to be used in subsequent transacts.
+ * </p>
+ * Committing an {@link InProgress} commits all the transacts that have been performed using
+ * that {@link InProgress}.
+ * </p>
+ * Rolling back and {@link InProgress} rolls back all the transacts that have been performed
+ * using that {@link InProgress}.
+ * </p>
+ * <pre>{@code
+ * do {
+ * let inProgress = try mentat.beginTransaction()
+ * let txReport = try inProgress.transact(transaction: "[[:db/add "a" :foo/long 22]]")
+ * let aEntid = txReport.entid(forTempId: "a")
+ * let report = try inProgress.transact(transaction: "[[:db/add "b" :foo/ref \(aEntid)] [:db/add "b" :foo/boolean true]]")
+ * try inProgress.commit()
+ * } catch {
+ * ...
+ * }
+ * }</pre>
+ * </p>
+ * {@link InProgress} also provides a number of functions to generating an builder to assert datoms
+ * programatically. The two types of builder are {@link InProgressBuilder} and {@link EntityBuilder}.
+ * </p>
+ * {@link InProgressBuilder} takes the current {@link InProgress} and provides a programmatic
+ * interface to add and retract values from entities for which there exists an `Entid`. The provided
+ * {@link InProgress} is used to perform the transacts.
+ * </p>
+ * <pre>{@code
+ * long aEntid = txReport.getEntidForTempId("a");
+ * long bEntid = txReport.getEntidForTempId("b");
+ * InProgress inProgress = mentat.beginTransaction();
+ * InProgressBuilder builder = inProgress.builder();
+ * builder.add(bEntid, ":foo/boolean", true);
+ * builder.add(aEntid, ":foo/instant", newDate);
+ * inProgress  = builder.transact().getInProgress();
+ * inProgress.transact("[[:db/add \(aEntid) :foo/long 22]]");
+ * inProgress.commit();
+ * }
+ * }</pre>
+ * </p>
+ * {@link EntityBuilder} takes the current {@link InProgress} and either an `Entid` or a `tempid` to
+ * provide a programmatic interface to add and retract values from a specific entity. The provided
+ * {@link InProgress} is used to perform the transacts.
+ * </p>
+ * <pre>{@code
+ * long aEntid = txReport.getEntidForTempId("a");
+ * long bEntid = txReport.getEntidForTempId("b");
+ * InProgress inProgress = mentat.beginTransaction();
+ * EntityBuilder builder = inProgress.builderForEntid(bEntid);
+ * builder.add(":foo/boolean", true);
+ * builder.add(":foo/instant", newDate);
+ * inProgress  = builder.transact().getInProgress();
+ * inProgress.transact("[[:db/add \(aEntid) :foo/long 22]]");
+ * inProgress.commit();
+ * }</pre>
+ */
+public class InProgress extends RustObject {
+
+    public InProgress(Pointer pointer) {
+        this.rawPointer = pointer;
+    }
+
+    /**
+     * Creates an {@link InProgressBuilder}  using this {@link InProgress} .
+     *
+     * @return an {@link InProgressBuilder} for this {@link InProgress}
+     */
+    public InProgressBuilder builder() {
+        this.validate();
+        InProgressBuilder builder = new InProgressBuilder(JNA.INSTANCE.in_progress_builder(this.rawPointer));
+        this.rawPointer = null;
+        return builder;
+    }
+
+    /**
+     * Creates an `EntityBuilder` using this `InProgress` for the entity with `entid`.
+     *
+     *
+     * @param entid The `Entid` for this entity.
+     * @return  an `EntityBuilder` for this `InProgress`
+     */
+    public EntityBuilder builderForEntid(long entid){
+        this.validate();
+        EntityBuilder builder = new EntityBuilder(JNA.INSTANCE.in_progress_entity_builder_from_entid(this.rawPointer, entid));
+        this.rawPointer = null;
+        return builder;
+    }
+
+    /**
+     * Creates an `EntityBuilder` using this `InProgress` for a new entity with `tempid`.
+     *
+     *
+     * @param tempid The temporary identifier for this entity.
+     * @return  an `EntityBuilder` for this `InProgress`
+     */
+    public EntityBuilder builderForTempid(String tempid){
+        this.validate();
+        EntityBuilder builder = new EntityBuilder(JNA.INSTANCE.in_progress_entity_builder_from_temp_id(this.rawPointer, tempid));
+        this.rawPointer = null;
+        return builder;
+    }
+
+    /**
+     Transacts the `transaction`
+
+     This does not commit the transaction. In order to do so, `commit` can be called.
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the transaction failed.
+     - Throws: `ResultError.empty` if no `TxReport` is returned from the transact.
+
+     - Returns: The `TxReport` generated by the transact.
+     */
+    /**
+     * Transacts the `transaction`
+     *
+     * This does not commit the transaction. In order to do so, `commit` can be called.
+     *
+     * TODO throw Exception on result failure.
+     *
+     * @param transaction   The EDN string to be transacted.
+     * @return  The `TxReport` generated by the transact.
+     */
+    public TxReport transact(String transaction) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_transact(this.rawPointer, transaction);
+        if (result.isFailure()) {
+            Log.e("InProgress", result.err);
+            return null;
+        }
+        return new TxReport(result.ok);
+    }
+
+    /**
+     * Commits all the transacts that have been performed on this `InProgress`, either directly
+     * or through a Builder. This consumes the pointer associated with this {@link InProgress} such
+     * that no further assertions can be performed after the `commit` has completed.
+     *
+     * TODO throw exception if error occurs
+     */
+    public void commit() {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_commit(this.rawPointer);
+        this.rawPointer = null;
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Rolls back all the transacts that have been performed on this `InProgress`, either directly
+     * or through a Builder.
+     *
+     * TODO throw exception if error occurs
+     */
+    public void rollback() {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_rollback(this.rawPointer);
+        this.rawPointer = null;
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    @Override
+    public void close() throws IOException {
+        if (this.rawPointer != null) {
+            JNA.INSTANCE.in_progress_destroy(this.rawPointer);
+        }
+    }
+}

sdks/android/Mentat/library/src/main/java/com/mozilla/mentat/InProgressBuilder.java

@@ -0,0 +1,382 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * Copyright 2018 Mozilla
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+ * this file except in compliance with the License. You may obtain a copy of the
+ * License at http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software distributed
+ * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License. */
+
+package com.mozilla.mentat;
+
+import android.util.Log;
+
+import com.sun.jna.Pointer;
+
+import java.io.IOException;
+import java.util.Date;
+import java.util.UUID;
+
+/**
+ * This class wraps a raw pointer that points to a Rust `InProgressBuilder` object.
+ *
+ * {@link InProgressBuilder} provides a programmatic interface to performing assertions for entities.
+ * It provides functions for adding and retracting values for attributes for an entity within
+ * an in progress transaction.
+ * <p/>
+ * The `transact` function will transact the assertions that have been added to the {@link InProgressBuilder}
+ * and pass back the {@link TxReport} that was generated by this transact and the {@link InProgress} that was
+ * used to perform the transact. This enables you to perform further transacts on the same {@link InProgress}
+ * before committing.
+ * <p/>
+ * <pre>{@code
+ * long aEntid = txReport.getEntidForTempId("a");
+ * long bEntid = txReport.getEntidForTempId("b");
+ * InProgressBuilder builder = mentat.getEntityBuilder();
+ * builder.add(aEntid, ":foo/boolean", true);
+ * builder.add(bEntid, ":foo/instant", newDate);
+ * InProgress inProgress = builder.transact().getInProgress();
+ * inProgress.transact("[[:db/add \(aEntid) :foo/long 22]]");
+ * inProgress.commit();
+ * }</pre>
+ * <p/>
+ * The `commit` function will transact and commit the assertions that have been added to the
+ * {@link InProgressBuilder}.
+ * It will consume the {@link InProgress} used to perform the transact. It returns the {@link TxReport}
+ * generated by the transact. After calling `commit`, a new transaction must be started by calling
+ * <pre>Mentat.beginTransaction()</pre> in order to perform further actions.
+ * <p/>
+ * <pre>{@code
+ * long aEntid = txReport.getEntidForTempId("a");
+ * long bEntid = txReport.getEntidForTempId("b");
+ * InProgressBuilder builder = mentat.getEntityBuilder();
+ * builder.add(aEntid, ":foo/boolean", true);
+ * builder.add(bEntid, ":foo/instant", newDate);
+ * builder.commit();
+ * }</pre>
+ */
+public class InProgressBuilder extends RustObject {
+
+    public InProgressBuilder(Pointer pointer) {
+        this.rawPointer = pointer;
+    }
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     *
+     * // TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(long entid, String keyword, long value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_add_long(this.rawPointer, entid, keyword, value);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void addRef(long entid, String keyword, long value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_add_ref(this.rawPointer, entid, keyword, value);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void addKeyword(long entid, String keyword, String value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_add_keyword(this.rawPointer, entid, keyword, value);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(long entid, String keyword, boolean value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_add_boolean(this.rawPointer, entid, keyword, value ? 1 : 0);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(long entid, String keyword, double value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_add_double(this.rawPointer, entid, keyword, value);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(long entid, String keyword, Date value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_add_timestamp(this.rawPointer, entid, keyword, value.getTime() * 1_000);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(long entid, String keyword, String value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_add_string(this.rawPointer, entid, keyword, value);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Asserts the value of attribute `keyword` to be the provided `value`.
+     * // TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be asserted
+     */
+    public void add(long entid, String keyword, UUID value) {
+        this.validate();
+
+        RustResult result = JNA.INSTANCE.in_progress_builder_add_uuid(this.rawPointer, entid, keyword, getPointerForUUID(value));
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(long entid, String keyword, long value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_retract_long(this.rawPointer, entid, keyword, value);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retractRef(long entid, String keyword, long value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_retract_ref(this.rawPointer, entid, keyword, value);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retractKeyword(long entid, String keyword, String value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_retract_keyword(this.rawPointer, entid, keyword, value);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(long entid, String keyword, boolean value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_retract_boolean(this.rawPointer, entid, keyword, value ? 1 : 0);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(long entid, String keyword, double value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_retract_double(this.rawPointer, entid, keyword, value);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(long entid, String keyword, Date value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_retract_timestamp(this.rawPointer, entid, keyword, value.getTime() * 1_000);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(long entid, String keyword, String value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_retract_string(this.rawPointer, entid, keyword, value);
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Retracts the value of attribute `keyword` from the provided `value`.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @param entid   The `Entid` of the entity to be touched.
+     * @param keyword   The name of the attribute in the format `:namespace/name`.
+     * @param value The value to be retracted
+     */
+    public void retract(long entid, String keyword, UUID value) {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_retract_uuid(this.rawPointer, entid, keyword, this.getPointerForUUID(value));
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+        }
+    }
+
+    /**
+     * Transacts the added assertions. This consumes the pointer associated with this {@link InProgressBuilder}
+     * such that no further assertions can be added after the `transact` has completed. To perform
+     * further assertions, use the {@link InProgress} inside the {@link InProgressTransactionResult}
+     * returned from this function.
+     * <p/>
+     * This does not commit the transaction. In order to do so, `commit` can be called on the
+     * {@link InProgress} inside the {@link InProgressTransactionResult} returned from this function.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @return A {@link InProgressTransactionResult} containing the current {@link InProgress} and
+     * the {@link TxReport}  generated by the transact.
+     */
+    public InProgressTransactionResult transact() {
+        this.validate();
+        InProgressTransactionResult result = JNA.INSTANCE.in_progress_builder_transact(this.rawPointer);
+        this.rawPointer = null;
+        return result;
+    }
+
+    /**
+     * Transacts the added assertions and commits. This consumes the pointer associated with this
+     * {@link InProgressBuilder} and the associated {@link InProgress} such that no further assertions
+     * can be added after the `commit` has completed.
+     * <p/>
+     * To perform further assertions, a new `{@link InProgress} or {@link InProgressBuilder} should be
+     * created.
+     *
+     * TODO throw exception if error occurs
+     *
+     * @return
+     */
+    public TxReport commit() {
+        this.validate();
+        RustResult result = JNA.INSTANCE.in_progress_builder_commit(this.rawPointer);
+        this.rawPointer = null;
+        if (result.isFailure()) {
+            Log.e("InProgressBuilder", result.err);
+            return null;
+        }
+
+        return new TxReport(result.ok);
+    }
+
+    @Override
+    public void close() throws IOException {
+        if (this.rawPointer != null) {
+            JNA.INSTANCE.in_progress_builder_destroy(this.rawPointer);
+        }
+    }
+}

sdks/android/Mentat/library/src/main/java/com/mozilla/mentat/InProgressTransactionResult.java

@@ -0,0 +1,56 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * Copyright 2018 Mozilla
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+ * this file except in compliance with the License. You may obtain a copy of the
+ * License at http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software distributed
+ * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License. */
+
+package com.mozilla.mentat;
+
+import android.util.Log;
+
+import com.sun.jna.Pointer;
+import com.sun.jna.Structure;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.List;
+
+public class InProgressTransactionResult extends Structure implements Closeable {
+    public static class ByReference extends InProgressTransactionResult implements Structure.ByReference {
+    }
+
+    public static class ByValue extends InProgressTransactionResult implements Structure.ByValue {
+    }
+
+    public Pointer inProgress;
+    public RustResult.ByReference result;
+
+    @Override
+    protected List<String> getFieldOrder() {
+        return Arrays.asList("inProgress", "result");
+    }
+
+    public InProgress getInProgress() {
+        return new InProgress(this.inProgress);
+    }
+    public TxReport getReport() {
+        if (this.result.isFailure()) {
+            Log.e("InProgressTransactionResult", this.result.err);
+            return null;
+        }
+
+        return new TxReport(this.result.ok);
+    }
+
+    @Override
+    public void close() throws IOException {
+        if (this.getPointer() != null) {
+            JNA.INSTANCE.destroy(this.getPointer());
+        }
+    }
+}

sdks/android/Mentat/library/src/main/java/com/mozilla/mentat/JNA.java

@@ -37,12 +37,72 @@ public interface JNA extends Library {
     void typed_value_result_set_destroy(Pointer obj);
     void typed_value_result_set_iter_destroy(Pointer obj);
     void tx_report_destroy(Pointer obj);
+    void in_progress_destroy(Pointer obj);
+    void in_progress_builder_destroy(Pointer obj);
+    void entity_builder_destroy(Pointer obj);
+
+    // caching
+    RustResult store_cache_attribute_forward(Pointer store, String attribute);
+    RustResult store_cache_attribute_reverse(Pointer store, String attribute);
+    RustResult store_cache_attribute_bi_directional(Pointer store, String attribute);
 
     // transact
     RustResult store_transact(Pointer store, String transaction);
     Pointer tx_report_entity_for_temp_id(Pointer report, String tempid);
     long tx_report_get_entid(Pointer report);
     long tx_report_get_tx_instant(Pointer report);
+    RustResult store_begin_transaction(Pointer store);
+
+    // in progress
+    RustResult in_progress_transact(Pointer in_progress, String transaction);
+    RustResult in_progress_commit(Pointer in_progress);
+    RustResult in_progress_rollback(Pointer in_progress);
+    Pointer in_progress_builder(Pointer in_progress);
+    Pointer in_progress_entity_builder_from_temp_id(Pointer in_progress, String temp_id);
+    Pointer in_progress_entity_builder_from_entid(Pointer in_progress, long entid);
+
+    // in_progress entity building
+    RustResult store_in_progress_builder(Pointer store);
+    RustResult in_progress_builder_add_string(Pointer builder, long entid, String kw, String value);
+    RustResult in_progress_builder_add_long(Pointer builder, long entid, String kw, long value);
+    RustResult in_progress_builder_add_ref(Pointer builder, long entid, String kw, long value);
+    RustResult in_progress_builder_add_keyword(Pointer builder, long entid, String kw, String value);
+    RustResult in_progress_builder_add_timestamp(Pointer builder, long entid, String kw, long value);
+    RustResult in_progress_builder_add_boolean(Pointer builder, long entid, String kw, int value);
+    RustResult in_progress_builder_add_double(Pointer builder, long entid, String kw, double value);
+    RustResult in_progress_builder_add_uuid(Pointer builder, long entid, String kw, Pointer value);
+    RustResult in_progress_builder_retract_string(Pointer builder, long entid, String kw, String value);
+    RustResult in_progress_builder_retract_long(Pointer builder, long entid, String kw, long value);
+    RustResult in_progress_builder_retract_ref(Pointer builder, long entid, String kw, long value);
+    RustResult in_progress_builder_retract_keyword(Pointer builder, long entid, String kw, String value);
+    RustResult in_progress_builder_retract_timestamp(Pointer builder, long entid, String kw, long value);
+    RustResult in_progress_builder_retract_boolean(Pointer builder, long entid, String kw, int value);
+    RustResult in_progress_builder_retract_double(Pointer builder, long entid, String kw, double value);
+    RustResult in_progress_builder_retract_uuid(Pointer builder, long entid, String kw, Pointer value);
+    InProgressTransactionResult in_progress_builder_transact(Pointer builder);
+    RustResult in_progress_builder_commit(Pointer builder);
+
+    // entity building
+    RustResult store_entity_builder_from_temp_id(Pointer store, String temp_id);
+    RustResult store_entity_builder_from_entid(Pointer store, long entid);
+    RustResult entity_builder_add_string(Pointer builder, String kw, String value);
+    RustResult entity_builder_add_long(Pointer builder, String kw, long value);
+    RustResult entity_builder_add_ref(Pointer builder, String kw, long value);
+    RustResult entity_builder_add_keyword(Pointer builder, String kw, String value);
+    RustResult entity_builder_add_boolean(Pointer builder, String kw, int value);
+    RustResult entity_builder_add_double(Pointer builder, String kw, double value);
+    RustResult entity_builder_add_timestamp(Pointer builder, String kw, long value);
+    RustResult entity_builder_add_uuid(Pointer builder, String kw, Pointer value);
+    RustResult entity_builder_retract_string(Pointer builder, String kw, String value);
+    RustResult entity_builder_retract_long(Pointer builder, String kw, long value);
+    RustResult entity_builder_retract_ref(Pointer builder, String kw, long value);
+    RustResult entity_builder_retract_keyword(Pointer builder, String kw, String value);
+    RustResult entity_builder_retract_boolean(Pointer builder, String kw, int value);
+    RustResult entity_builder_retract_double(Pointer builder, String kw, double value);
+    RustResult entity_builder_retract_timestamp(Pointer builder, String kw, long value);
+    RustResult entity_builder_retract_uuid(Pointer builder, String kw, Pointer value);
+    InProgressTransactionResult entity_builder_transact(Pointer builder);
+    RustResult entity_builder_commit(Pointer builder);
 
     // sync
     RustResult store_sync(Pointer store, String userUuid, String serverUri);
@@ -95,7 +155,7 @@ public interface JNA extends Library {
     String value_at_index_into_kw(Pointer rows, int index);
     String value_at_index_into_string(Pointer rows, int index);
     Pointer value_at_index_into_uuid(Pointer rows, int index);
-    long value_at_index_into_boolean(Pointer rows, int index);
+    int value_at_index_into_boolean(Pointer rows, int index);
     double value_at_index_into_double(Pointer rows, int index);
     long value_at_index_into_timestamp(Pointer rows, int index);
 }

sdks/android/Mentat/library/src/main/java/com/mozilla/mentat/Mentat.java

@@ -48,9 +48,38 @@ public class Mentat extends RustObject {
      */
     public Mentat(Pointer rawPointer) { this.rawPointer = rawPointer; }
 
+    /**
+     * Add an attribute to the cache. The {@link CacheDirection} determines how that attribute can be
+     * looked up.
+     *
+     * TODO: Throw an exception if cache action fails. https://github.com/mozilla/mentat/issues/700
+     *
+     * @param attribute The attribute to cache
+     * @param direction The direction the attribute should be keyed.
+     * FORWARD caches values for an attribute keyed by entity
+     * (i.e. find values and entities that have this attribute, or find values of attribute for an entity)
+     * REVERSE caches entities for an attribute keyed by value.
+     * (i.e. find entities that have a particular value for an attribute).
+     * BOTH adds an attribute such that it is cached in both directions.
+     */
+    public void cache(String attribute, CacheDirection direction) {
+        RustResult result = null;
+        switch (direction) {
+            case FORWARD:
+                result = JNA.INSTANCE.store_cache_attribute_forward(this.rawPointer, attribute);
+            case REVERSE:
+                result = JNA.INSTANCE.store_cache_attribute_reverse(this.rawPointer, attribute);
+            case BOTH:
+                result = JNA.INSTANCE.store_cache_attribute_bi_directional(this.rawPointer, attribute);
+        }
+        if (result.isFailure()) {
+            Log.e("Mentat", result.err);
+        }
+    }
+
     /**
      * Simple transact of an EDN string.
-     * TODO: Throw an exception if the transact fails
+     * TODO: Throw an exception if the transact fails. https://github.com/mozilla/mentat/issues/700
      * @param transaction   The string, as EDN, to be transacted.
      * @return  The {@link TxReport} of the completed transaction
      */
@@ -88,7 +117,7 @@ public class Mentat extends RustObject {
 
     /**
      * Retrieve a single value of an attribute for an Entity
-     * TODO: Throw an exception if there is no the result contains an error.
+     * TODO: Throw an exception if the result contains an error. https://github.com/mozilla/mentat/issues/700
      * @param attribute The string the attribute whose value is to be returned. The string is represented as `:namespace/name`.
      * @param entid The `Entid` of the entity we want the value from.
      * @return  The {@link TypedValue} containing the value of the attribute for the entity.
@@ -138,6 +167,92 @@ public class Mentat extends RustObject {
         JNA.INSTANCE.store_unregister_observer(rawPointer, key);
     }
 
+
+    /**
+     * Start a new transaction
+     *
+     * TODO: Throw an exception if the result contains an error. https://github.com/mozilla/mentat/issues/700
+     *
+     * @return The {@link InProgress} used to manage the transaction
+     */
+    public InProgress beginTransaction() {
+        RustResult result = JNA.INSTANCE.store_begin_transaction(this.rawPointer);
+        if (result.isSuccess()) {
+            return new InProgress(result.ok);
+        }
+
+        if (result.isFailure()) {
+            Log.i("Mentat", result.err);
+        }
+
+        return null;
+    }
+
+    /**
+     * Creates a new transaction ({@link InProgress}) and returns an {@link InProgressBuilder} for
+     * that transaction.
+     *
+     * TODO: Throw an exception if the result contains an error. https://github.com/mozilla/mentat/issues/700
+     *
+     * @return  an {@link InProgressBuilder} for a new transaction.
+     */
+    public InProgressBuilder entityBuilder() {
+        RustResult result = JNA.INSTANCE.store_in_progress_builder(this.rawPointer);
+        if (result.isSuccess()) {
+            return new InProgressBuilder(result.ok);
+        }
+
+        if (result.isFailure()) {
+            Log.i("Mentat", result.err);
+        }
+
+        return null;
+    }
+
+    /**
+     * Creates a new transaction ({@link InProgress}) and returns an {@link EntityBuilder} for the
+     * entity with `entid` for that transaction.
+     *
+     * TODO: Throw an exception if the result contains an error. https://github.com/mozilla/mentat/issues/700
+     *
+     * @param entid The `Entid` for this entity.
+     * @return  an {@link EntityBuilder} for a new transaction.
+     */
+    public EntityBuilder entityBuilder(long entid) {
+        RustResult result = JNA.INSTANCE.store_entity_builder_from_entid(this.rawPointer, entid);
+        if (result.isSuccess()) {
+            return new EntityBuilder(result.ok);
+        }
+
+        if (result.isFailure()) {
+            Log.i("Mentat", result.err);
+        }
+
+        return null;
+    }
+
+    /**
+     * Creates a new transaction ({@link InProgress}) and returns an {@link EntityBuilder} for a new
+     * entity with `tempId` for that transaction.
+     *
+     * TODO: Throw an exception if the result contains an error. https://github.com/mozilla/mentat/issues/700
+     *
+     * @param tempId    The temporary identifier for this entity.
+     * @return  an {@link EntityBuilder} for a new transaction.
+     */
+    public EntityBuilder entityBuilder(String tempId) {
+        RustResult result = JNA.INSTANCE.store_entity_builder_from_temp_id(this.rawPointer, tempId);
+        if (result.isSuccess()) {
+            return new EntityBuilder(result.ok);
+        }
+
+        if (result.isFailure()) {
+            Log.i("Mentat", result.err);
+        }
+
+        return null;
+    }
+
     @Override
     public void close() {
         if (this.rawPointer != null) {

sdks/android/Mentat/library/src/main/java/com/mozilla/mentat/Query.java

@@ -76,7 +76,7 @@ import java.util.UUID;
  * <pre>{@code
  * String query = "[: find ?a .\n" +
  *          "        : where ... ]";
- * mentat.query(query).runScalar(new ScalarResultHandler() {
+ * mentat.query(query).run(new ScalarResultHandler() {
  *      @Override
  *      public void handleValue(TypedValue value) {
  *          ...
@@ -88,7 +88,7 @@ import java.util.UUID;
  * <pre>{@code
  * String query = "[: find [?a ...]\n" +
  *          "        : where ... ]";
- * mentat.query(query).runColl(new ScalarResultHandler() {
+ * mentat.query(query).run(new ScalarResultHandler() {
  *      @Override
  *      public void handleList(CollResult list) {
  *          ...
@@ -100,7 +100,7 @@ import java.util.UUID;
  * <pre>{@code
  * String query = "[: find [?a ?b ?c]\n" +
  *          "        : where ... ]";
- * mentat.query(query).runTuple(new TupleResultHandler() {
+ * mentat.query(query).run(new TupleResultHandler() {
  *      @Override
  *      public void handleRow(TupleResult row) {
  *          ...
@@ -121,7 +121,7 @@ public class Query extends RustObject {
      * @param value The value to be bound
      * @return  This {@link Query} such that further function can be called.
      */
-    Query bindLong(String varName, long value) {
+    Query bind(String varName, long value) {
         this.validate();
         JNA.INSTANCE.query_builder_bind_long(this.rawPointer, varName, value);
         return this;
@@ -173,7 +173,7 @@ public class Query extends RustObject {
      * @param value The value to be bound
      * @return  This {@link Query} such that further function can be called.
      */
-    Query bindBoolean(String varName, boolean value) {
+    Query bind(String varName, boolean value) {
         this.validate();
         JNA.INSTANCE.query_builder_bind_boolean(this.rawPointer, varName, value ? 1 : 0);
         return this;
@@ -186,7 +186,7 @@ public class Query extends RustObject {
      * @param value The value to be bound
      * @return  This {@link Query} such that further function can be called.
      */
-    Query bindDouble(String varName, double value) {
+    Query bind(String varName, double value) {
         this.validate();
         JNA.INSTANCE.query_builder_bind_double(this.rawPointer, varName, value);
         return this;
@@ -199,7 +199,7 @@ public class Query extends RustObject {
      * @param value The value to be bound
      * @return  This {@link Query} such that further function can be called.
      */
-    Query bindDate(String varName, Date value) {
+    Query bind(String varName, Date value) {
         this.validate();
         long timestamp = value.getTime() * 1000;
         JNA.INSTANCE.query_builder_bind_timestamp(this.rawPointer, varName, timestamp);
@@ -213,7 +213,7 @@ public class Query extends RustObject {
      * @param value The value to be bound
      * @return  This {@link Query} such that further function can be called.
      */
-    Query bindString(String varName, String value) {
+    Query bind(String varName, String value) {
         this.validate();
         JNA.INSTANCE.query_builder_bind_string(this.rawPointer, varName, value);
         return this;
@@ -226,15 +226,9 @@ public class Query extends RustObject {
      * @param value The value to be bound
      * @return  This {@link Query} such that further function can be called.
      */
-    Query bindUUID(String varName, UUID value) {
+    Query bind(String varName, UUID value) {
         this.validate();
-        ByteBuffer bb = ByteBuffer.wrap(new byte[16]);
+        JNA.INSTANCE.query_builder_bind_uuid(this.rawPointer, varName, getPointerForUUID(value));
-        bb.putLong(value.getMostSignificantBits());
-        bb.putLong(value.getLeastSignificantBits());
-        byte[] bytes = bb.array();
-        final Pointer bytesNativeArray = new Memory(bytes.length);
-        bytesNativeArray.write(0, bytes, 0, bytes.length);
-        JNA.INSTANCE.query_builder_bind_uuid(this.rawPointer, varName, bytesNativeArray);
         return this;
     }
 
@@ -262,7 +256,7 @@ public class Query extends RustObject {
      * TODO: Throw an exception if the query raw pointer has been consumed or the query fails to execute
      * @param handler   the handler to call with the results of this query
      */
-    void runScalar(final ScalarResultHandler handler) {
+    void run(final ScalarResultHandler handler) {
         this.validate();
         RustResult result = JNA.INSTANCE.query_builder_execute_scalar(rawPointer);
         rawPointer = null;
@@ -285,7 +279,7 @@ public class Query extends RustObject {
      * TODO: Throw an exception if the query raw pointer has been consumed or the query fails to execute
      * @param handler   the handler to call with the results of this query
      */
-    void runColl(final CollResultHandler handler) {
+    void run(final CollResultHandler handler) {
         this.validate();
         RustResult result = JNA.INSTANCE.query_builder_execute_coll(rawPointer);
         rawPointer = null;
@@ -303,7 +297,7 @@ public class Query extends RustObject {
      * TODO: Throw an exception if the query raw pointer has been consumed or the query fails to execute
      * @param handler   the handler to call with the results of this query
      */
-    void runTuple(final TupleResultHandler handler) {
+    void run(final TupleResultHandler handler) {
         this.validate();
         RustResult result = JNA.INSTANCE.query_builder_execute_tuple(rawPointer);
         rawPointer = null;

sdks/android/Mentat/library/src/main/java/com/mozilla/mentat/RustObject.java

@@ -10,9 +10,12 @@
 
 package com.mozilla.mentat;
 
+import com.sun.jna.Memory;
 import com.sun.jna.Pointer;
 
 import java.io.Closeable;
+import java.nio.ByteBuffer;
+import java.util.UUID;
 
 /**
  * Base class that wraps an non-optional {@link Pointer} representing a pointer to a Rust object.
@@ -31,4 +34,22 @@ abstract class RustObject implements Closeable {
             throw new NullPointerException(this.getClass() + " consumed");
         }
     }
+
+    public Pointer getPointerForUUID(UUID uuid) {
+        ByteBuffer bb = ByteBuffer.wrap(new byte[16]);
+        bb.putLong(uuid.getMostSignificantBits());
+        bb.putLong(uuid.getLeastSignificantBits());
+        byte[] bytes = bb.array();
+        final Pointer bytesNativeArray = new Memory(bytes.length);
+        bytesNativeArray.write(0, bytes, 0, bytes.length);
+        return bytesNativeArray;
+    }
+
+    public UUID getUUIDFromPointer(Pointer uuidPtr) {
+        byte[] bytes = uuidPtr.getByteArray(0, 16);
+        ByteBuffer bb = ByteBuffer.wrap(bytes);
+        long high = bb.getLong();
+        long low = bb.getLong();
+        return new UUID(high, low);
+    }
 }

sdks/android/Mentat/library/src/main/java/com/mozilla/mentat/TupleResult.java

@@ -126,7 +126,7 @@ public class TupleResult extends RustObject {
      */
     public Date asDate(Integer index) {
         this.validate();
-        return new Date(JNA.INSTANCE.value_at_index_into_timestamp(this.rawPointer, index));
+        return new Date(JNA.INSTANCE.value_at_index_into_timestamp(this.rawPointer, index) * 1_000);
     }
 
     /**
@@ -150,13 +150,7 @@ public class TupleResult extends RustObject {
      */
     public UUID asUUID(Integer index) {
         this.validate();
-        Pointer uuidPtr = JNA.INSTANCE.value_at_index_into_uuid(this.rawPointer, index);
+        return getUUIDFromPointer(JNA.INSTANCE.value_at_index_into_uuid(this.rawPointer, index));
-        byte[] bytes = uuidPtr.getByteArray(0, 16);
-        ByteBuffer bb = ByteBuffer.wrap(bytes);
-        long high = bb.getLong();
-        long low = bb.getLong();
-
-        return new UUID(high, low);
     }
 
     @Override

sdks/android/Mentat/library/src/main/java/com/mozilla/mentat/TypedValue.java

@@ -137,12 +137,7 @@ public class TypedValue extends RustObject {
      */
     public UUID asUUID() {
         if (!this.isConsumed()) {
-            Pointer uuidPtr = JNA.INSTANCE.typed_value_into_uuid(this.rawPointer);
+            this.value = getUUIDFromPointer(JNA.INSTANCE.typed_value_into_uuid(this.rawPointer));
-            byte[] bytes = uuidPtr.getByteArray(0, 16);
-            ByteBuffer bb = ByteBuffer.wrap(bytes);
-            long high = bb.getLong();
-            long low = bb.getLong();
-            this.value = new UUID(high, low);
             this.rawPointer = null;
         }
         return (UUID)this.value;

sdks/swift/Mentat/Mentat.xcodeproj/project.pbxproj

@@ -7,6 +7,9 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		7B64E44D209094520063909F /* InProgressBuilder.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7B64E44A209094510063909F /* InProgressBuilder.swift */; };
+		7B64E44E209094520063909F /* EntityBuilder.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7B64E44B209094510063909F /* EntityBuilder.swift */; };
+		7B64E44F209094520063909F /* InProgress.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7B64E44C209094520063909F /* InProgress.swift */; };
 		7B74483D208DF667006CFFB0 /* Result+Unwrap.swift in Sources */ = {isa = PBXBuildFile; fileRef = 7B74483C208DF667006CFFB0 /* Result+Unwrap.swift */; };
 		7BAE75A22089020E00895D37 /* libmentat_ffi.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 7BEB7D23207BE2AF000369AD /* libmentat_ffi.a */; };
 		7BAE75A42089022B00895D37 /* libsqlite3.tbd in Frameworks */ = {isa = PBXBuildFile; fileRef = 7BAE75A32089022B00895D37 /* libsqlite3.tbd */; };
@@ -39,6 +42,9 @@
 /* End PBXContainerItemProxy section */
 
 /* Begin PBXFileReference section */
+		7B64E44A209094510063909F /* InProgressBuilder.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = InProgressBuilder.swift; sourceTree = "<group>"; };
+		7B64E44B209094510063909F /* EntityBuilder.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = EntityBuilder.swift; sourceTree = "<group>"; };
+		7B64E44C209094520063909F /* InProgress.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = InProgress.swift; sourceTree = "<group>"; };
 		7B74483C208DF667006CFFB0 /* Result+Unwrap.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; name = "Result+Unwrap.swift"; path = "Mentat/Extensions/Result+Unwrap.swift"; sourceTree = SOURCE_ROOT; };
 		7B911E1A2085081D000998CB /* libtoodle.a */ = {isa = PBXFileReference; lastKnownFileType = archive.ar; name = libtoodle.a; path = "../../../../sync-storage-prototype/rust/target/universal/release/libtoodle.a"; sourceTree = "<group>"; };
 		7BAE75A32089022B00895D37 /* libsqlite3.tbd */ = {isa = PBXFileReference; lastKnownFileType = "sourcecode.text-based-dylib-definition"; name = libsqlite3.tbd; path = usr/lib/libsqlite3.tbd; sourceTree = SDKROOT; };
@@ -196,6 +202,9 @@
 		7BEB7D26207BE5BB000369AD /* Transact */ = {
 			isa = PBXGroup;
 			children = (
+				7B64E44B209094510063909F /* EntityBuilder.swift */,
+				7B64E44C209094520063909F /* InProgress.swift */,
+				7B64E44A209094510063909F /* InProgressBuilder.swift */,
 				7BEB7D2B207D03DA000369AD /* TxReport.swift */,
 			);
 			path = Transact;
@@ -321,8 +330,11 @@
 				7BDB96CC207B7684009D0651 /* Errors.swift in Sources */,
 				7BDB96B02077C38E009D0651 /* Mentat.swift in Sources */,
 				7BDB96B72077C38E009D0651 /* TypedValue.swift in Sources */,
+				7B64E44E209094520063909F /* EntityBuilder.swift in Sources */,
+				7B64E44D209094520063909F /* InProgressBuilder.swift in Sources */,
 				7BDB96B52077C38E009D0651 /* TupleResult.swift in Sources */,
 				7B74483D208DF667006CFFB0 /* Result+Unwrap.swift in Sources */,
+				7B64E44F209094520063909F /* InProgress.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

sdks/swift/Mentat/Mentat.xcodeproj/xcshareddata/xcschemes/Mentat Debug.xcscheme

@@ -37,14 +37,6 @@
                BlueprintName = "MentatTests"
                ReferencedContainer = "container:Mentat.xcodeproj">
             </BuildableReference>
-            <SkippedTests>
-               <Test
-                  Identifier = "MentatTests/testBindBoolean()">
-               </Test>
-               <Test
-                  Identifier = "MentatTests/testBindDate()">
-               </Test>
-            </SkippedTests>
          </TestableReference>
       </Testables>
       <MacroExpansion>

sdks/swift/Mentat/Mentat/Errors/Errors.swift

@@ -1,4 +1,3 @@
-//
 /* Copyright 2018 Mozilla
  *
  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use

sdks/swift/Mentat/Mentat/Mentat.swift

@@ -29,6 +29,12 @@ protocol Observable {
     func unregister(key: String)
 }
 
+enum CacheDirection {
+    case forward;
+    case reverse;
+    case both;
+}
+
 /**
  The primary class for accessing Mentat's API.
  This class provides all of the basic API that can be found in Mentat's Store struct.
@@ -56,11 +62,36 @@ class Mentat: RustObject {
         self.init(raw: store_open(storeURI))
     }
 
+    /**
+     Add an attribute to the cache. The {@link CacheDirection} determines how that attribute can be
+     looked up.
+
+     - Parameter attribute: The attribute to cache
+     - Parameter direction: The direction the attribute should be keyed.
+        `forward` caches values for an attribute keyed by entity
+        (i.e. find values and entities that have this attribute, or find values of attribute for an entity)
+        `reverse` caches entities for an attribute keyed by value.
+        (i.e. find entities that have a particular value for an attribute).
+        `both` adds an attribute such that it is cached in both directions.
+
+     - Throws: `ResultError.error` if an error occured while trying to cache the attribute.
+     */
+    func cache(attribute: String, direction: CacheDirection) throws {
+        switch direction {
+        case .forward:
+            try store_cache_attribute_forward(self.raw, attribute).pointee.tryUnwrap()
+        case .reverse:
+            try store_cache_attribute_reverse(self.raw, attribute).pointee.tryUnwrap()
+        case .both:
+            try store_cache_attribute_bi_directional(self.raw, attribute).pointee.tryUnwrap()
+        }
+    }
+
     /**
     Simple transact of an EDN string.
      - Parameter transaction: The string, as EDN, to be transacted
 
-     - Throws: `MentatError` if the an error occured during the transaction, or the TxReport is nil.
+     - Throws: `ResultError.error` if the an error occured during the transaction, or the TxReport is nil.
 
      - Returns: The `TxReport` of the completed transaction
     */
@@ -69,8 +100,67 @@ class Mentat: RustObject {
         return TxReport(raw: try result.unwrap())
     }
 
+    /**
+     Start a new transaction.
+
+     - Throws: `ResultError.error` if the creation of the transaction fails.
+     - Throws: `ResultError.empty` if no `InProgress` is created.
+
+     - Returns: The `InProgress` used to manage the transaction
+     */
+    func beginTransaction() throws -> InProgress {
+        let result = store_begin_transaction(self.raw).pointee;
+        return InProgress(raw: try result.unwrap())
+    }
+
+    /**
+     Creates a new transaction (`InProgress`) and returns an `InProgressBuilder` for that transaction.
+
+     - Throws: `ResultError.error` if the creation of the transaction fails.
+     - Throws: `ResultError.empty` if no `InProgressBuilder` is created.
+
+     - Returns: an `InProgressBuilder` for this `InProgress`
+     */
+    func entityBuilder() throws -> InProgressBuilder {
+        let result = store_in_progress_builder(self.raw).pointee
+        return InProgressBuilder(raw: try result.unwrap())
+    }
+
+    /**
+     Creates a new transaction (`InProgress`) and returns an `EntityBuilder` for the entity with `entid`
+    for that transaction.
+
+     - Parameter entid: The `Entid` for this entity.
+
+     - Throws: `ResultError.error` if the creation of the transaction fails.
+     - Throws: `ResultError.empty` if no `EntityBuilder` is created.
+
+     - Returns: an `EntityBuilder` for this `InProgress`
+     */
+    func entityBuilder(forEntid entid: Entid) throws -> EntityBuilder {
+        let result = store_entity_builder_from_entid(self.raw, entid).pointee
+        return EntityBuilder(raw: try result.unwrap())
+    }
+
+    /**
+     Creates a new transaction (`InProgress`) and returns an `EntityBuilder` for a new entity with `tempId`
+    for that transaction.
+
+     - Parameter tempId: The temporary identifier for this entity.
+
+     - Throws: `ResultError.error` if the creation of the transaction fails.
+     - Throws: `ResultError.empty` if no `EntityBuilder` is created.
+
+     - Returns: an `EntityBuilder` for this `InProgress`
+     */
+    func entityBuilder(forTempId tempId: String) throws -> EntityBuilder {
+        let result = store_entity_builder_from_temp_id(self.raw, tempId).pointee
+        return EntityBuilder(raw: try result.unwrap())
+    }
+
     /**
      Get the the `Entid` of the attribute.
+
      - Parameter attribute: The string represeting the attribute whose `Entid` we are after.
      The string is represented as `:namespace/name`.
 

sdks/swift/Mentat/Mentat/Transact/EntityBuilder.swift

@@ -0,0 +1,355 @@
+/* Copyright 2018 Mozilla
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+ * this file except in compliance with the License. You may obtain a copy of the
+ * License at http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software distributed
+ * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License. */
+
+import Foundation
+import MentatStore
+
+/**
+ This class wraps a raw pointer that points to a Rust `EntityBuilder<InProgressBuilder>` object.
+
+ `EntityBuilder` provides a programmatic interface to performing assertions on a specific entity.
+ It provides functions for adding and retracting values for attributes for an entity within
+ an in progress transaction.
+
+ The `transact` function will transact the assertions that have been added to the `EntityBuilder`
+ and pass back the `TxReport` that was generated by this transact and the `InProgress` that was
+ used to perform the transact. This enables you to perform further transacts on the same `InProgress`
+ before committing.
+
+ ```
+ let aEntid = txReport.entid(forTempId: "a")
+ let bEntid = txReport.entid(forTempId: "b")
+ do {
+    let builder = try mentat.entityBuilder(forEntid: bEntid)
+    try builder.add(keyword: ":foo/boolean", boolean: true)
+    try builder.add(keyword: ":foo/instant", date: newDate)
+    let (inProgress, report) = try builder.transact()
+    try inProgress.transact(transaction: "[[:db/add \(aEntid) :foo/long 22]]")
+    try inProgress.commit()
+ } catch {
+    ...
+ }
+ ```
+
+ The `commit` function will transact and commit the assertions that have been added to the `EntityBuilder`.
+ It will consume the `InProgress` used to perform the transact. It returns the `TxReport` generated by
+ the transact. After calling `commit`, a new transaction must be started by calling `Mentat.beginTransaction()`
+ in order to perform further actions.
+
+ ```
+ let aEntid = txReport.entid(forTempId: "a")
+ do {
+     let builder = try mentat.entityBuilder(forEntid: aEntid)
+     try builder.add(keyword: ":foo/boolean", boolean: true)
+     try builder.add(keyword: ":foo/instant", date: newDate)
+     let report = try builder.commit()
+     ...
+ } catch {
+    ...
+ }
+ ```
+ */
+class EntityBuilder: OptionalRustObject {
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/long`.
+     */
+    func add(keyword: String, long value: Int64) throws {
+        try entity_builder_add_long(try self.validPointer(), keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/ref`.
+     */
+    func add(keyword: String, reference value: Int64) throws {
+        try entity_builder_add_ref(try self.validPointer(), keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/keyword`.
+     */
+    func add(keyword: String, keyword value: String) throws {
+        try entity_builder_add_keyword(try self.validPointer(), keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/boolean`.
+     */
+    func add(keyword: String, boolean value: Bool) throws {
+        try entity_builder_add_boolean(try self.validPointer(), keyword, value ? 1 : 0).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/double`.
+     */
+    func add(keyword: String, double value: Double) throws {
+        try entity_builder_add_double(try self.validPointer(), keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/instant`.
+     */
+    func add(keyword: String, date value: Date) throws {
+        try entity_builder_add_timestamp(try self.validPointer(), keyword, value.toMicroseconds()).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/string`.
+     */
+    func add(keyword: String, string value: String) throws {
+        try entity_builder_add_string(try self.validPointer(), keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/uuid`.
+     */
+    func add(keyword: String, uuid value: UUID) throws {
+        var rawUuid = value.uuid
+        let _ = try withUnsafePointer(to: &rawUuid) { uuidPtr in
+            try entity_builder_add_uuid(try self.validPointer(), keyword, uuidPtr).pointee.tryUnwrap()
+        }
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/long`.
+     */
+    func retract(keyword: String, long value: Int64) throws {
+        try entity_builder_retract_long(try self.validPointer(), keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/ref`.
+     */
+    func retract(keyword: String, reference value: Int64) throws {
+        try entity_builder_retract_ref(try self.validPointer(), keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/keyword`.
+     */
+    func retract(keyword: String, keyword value: String) throws {
+        try entity_builder_retract_keyword(try self.validPointer(), keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/boolean`.
+     */
+    func retract(keyword: String, boolean value: Bool) throws {
+        try entity_builder_retract_boolean(try self.validPointer(), keyword, value ? 1 : 0).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/double`.
+     */
+    func retract(keyword: String, double value: Double) throws {
+        try entity_builder_retract_double(try self.validPointer(), keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/instant`.
+     */
+    func retract(keyword: String, date value: Date) throws {
+        try entity_builder_retract_timestamp(try self.validPointer(), keyword, value.toMicroseconds()).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/string`.
+     */
+    func retract(keyword: String, string value: String) throws {
+        try entity_builder_retract_string(try self.validPointer(), keyword, value).pointee.tryUnwrap()
+    }
+
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value`.
+
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/uuid`.
+     */
+    func retract(keyword: String, uuid value: UUID) throws {
+        var rawUuid = value.uuid
+        let _ = try withUnsafePointer(to: &rawUuid) { uuidPtr in
+            try entity_builder_retract_uuid(try self.validPointer(), keyword, uuidPtr).pointee.tryUnwrap()
+        }
+    }
+
+    /**
+     Transacts the added assertions. This consumes the pointer associated with this `EntityBuilder`
+     such that no further assertions can be added after the `transact` has completed. To perform
+     further assertions, use the `InProgress` returned from this function.
+
+     This does not commit the transaction. In order to do so, `commit` can be called on the `InProgress` returned
+     from this function.
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if an error occured during the execution of the transact.
+
+     - Returns: The current `InProgress` and the `TxReport` generated by the transact.
+    */
+    func transact() throws -> (InProgress, TxReport?) {
+        defer {
+            self.raw = nil
+        }
+        let result = entity_builder_transact(try self.validPointer()).pointee
+        let inProgress = InProgress(raw: result.inProgress)
+        guard let report = try result.result.pointee.tryUnwrap() else {
+            return (inProgress, nil)
+        }
+        return (inProgress, TxReport(raw: report))
+    }
+
+    /**
+     Transacts the added assertions and commits. This consumes the pointer associated with this `EntityBuilder`
+     and the associated `InProgress` such that no further assertions can be added after the `commit` has completed.
+     To perform further assertions, a new `InProgress` or `EntityBuilder` should be created.
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if an error occured during the execution of the transact.
+
+     - Returns: The `TxReport` generated by the transact.
+     */
+    func commit() throws -> TxReport {
+        defer {
+            self.raw = nil
+        }
+        return TxReport(raw: try entity_builder_commit(try self.validPointer()).pointee.unwrap())
+    }
+    
+    override func cleanup(pointer: OpaquePointer) {
+        entity_builder_destroy(pointer)
+    }
+}

sdks/swift/Mentat/Mentat/Transact/InProgress.swift

@@ -0,0 +1,184 @@
+/* Copyright 2018 Mozilla
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+ * this file except in compliance with the License. You may obtain a copy of the
+ * License at http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software distributed
+ * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License. */
+
+import Foundation
+import MentatStore
+
+/**
+ This class wraps a raw pointer that points to a Rust `InProgress` object.
+
+ `InProgress` allows for multiple transacts to be performed in a single transaction.
+ Each transact performed results in a `TxReport` that can be used to gather information
+ to be used in subsequent transacts.
+
+ Committing an `InProgress` commits all the transacts that have been performed using
+ that `InProgress`.
+
+ Rolling back and `InProgress` rolls back all the transacts that have been performed
+ using that `InProgress`.
+
+ ```
+ do {
+     let inProgress = try mentat.beginTransaction()
+     let txReport = try inProgress.transact(transaction: "[[:db/add "a" :foo/long 22]]")
+     let aEntid = txReport.entid(forTempId: "a")
+     let report = try inProgress.transact(transaction: "[[:db/add "b" :foo/ref \(aEntid)] [:db/add "b" :foo/boolean true]]")
+     try inProgress.commit()
+ } catch {
+    ...
+ }
+ ```
+
+ `InProgress` also provides a number of functions to generating an builder to assert datoms programatically.
+ The two types of builder are `InProgressBuilder` and `EntityBuilder`.
+
+ `InProgressBuilder` takes the current `InProgress` and provides a programmatic interface to add
+ and retract values from entities for which there exists an `Entid`. The provided `InProgress`
+ is used to perform the transacts.
+
+ ```
+ let aEntid = txReport.entid(forTempId: "a")
+ let bEntid = txReport.entid(forTempId: "b")
+ do {
+     let inProgress = try mentat.beginTransaction()
+     let builder = try inProgress.builder()
+     try builder.add(entid: bEntid, keyword: ":foo/boolean", boolean: true)
+     try builder.add(entid: aEntid, keyword: ":foo/instant", date: newDate)
+     let (inProgress, report) = try builder.transact()
+     try inProgress.transact(transaction: "[[:db/add \(aEntid) :foo/long 22]]")
+     try inProgress.commit()
+ } catch {
+    ...
+ }
+ ```
+
+`EntityBuilder` takes the current `InProgress` and either an `Entid` or a `tempid` to provide
+ a programmatic interface to add and retract values from a specific entity. The provided `InProgress`
+ is used to perform the transacts.
+
+ ```
+ do {
+     let transaction = try mentat.beginTransaction()
+     let builder = try transaction.builder(forTempId: "b")
+     try builder.add(keyword: ":foo/boolean", boolean: true)
+     try builder.add(keyword: ":foo/instant", date: newDate)
+     let (inProgress, report) = try builder.transact()
+     let bEntid = report.entid(forTempId: "b")
+     try inProgress.transact(transaction: "[[:db/add \(bEntid) :foo/long 22]]")
+     try inProgress.commit()
+ } catch {
+    ...
+ }
+ ```
+ */
+class InProgress: OptionalRustObject {
+
+    /**
+     Creates an `InProgressBuilder` using this `InProgress`.
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the `InProgress`
+     has already been committed, or converted into a Builder.
+
+     - Returns: an `InProgressBuilder` for this `InProgress`
+     */
+    func builder() throws -> InProgressBuilder {
+        defer {
+            self.raw = nil
+        }
+        return InProgressBuilder(raw: in_progress_builder(try self.validPointer()))
+    }
+
+    /**
+     Creates an `EntityBuilder` using this `InProgress` for the entity with `entid`.
+
+     - Parameter entid: The `Entid` for this entity.
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the `InProgress`
+     has already been committed, or converted into a Builder.
+
+     - Returns: an `EntityBuilder` for this `InProgress`
+     */
+    func builder(forEntid entid: Int64) throws -> EntityBuilder {
+        defer {
+            self.raw = nil
+        }
+        return EntityBuilder(raw: in_progress_entity_builder_from_entid(try self.validPointer(), entid))
+    }
+
+    /**
+     Creates an `EntityBuilder` using this `InProgress` for a new entity with `tempId`.
+
+     - Parameter tempId: The temporary identifier for this entity.
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the `InProgress`
+     has already been committed, or converted into a Builder.
+
+     - Returns: an `EntityBuilder` for this `InProgress`
+     */
+    func builder(forTempId tempId: String) throws -> EntityBuilder {
+        defer {
+            self.raw = nil
+        }
+        return EntityBuilder(raw: in_progress_entity_builder_from_temp_id(try self.validPointer(), tempId))
+    }
+
+    /**
+     Transacts the `transaction`
+
+     This does not commit the transaction. In order to do so, `commit` can be called.
+
+     - Parameter transaction: The EDN string to be transacted.
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the transaction failed.
+     - Throws: `ResultError.empty` if no `TxReport` is returned from the transact.
+
+     - Returns: The `TxReport` generated by the transact.
+     */
+    func transact(transaction: String) throws -> TxReport {
+        let result = in_progress_transact(try self.validPointer(), transaction).pointee
+        return TxReport(raw: try result.unwrap())
+    }
+
+    /**
+         Commits all the transacts that have been performed on this `InProgress`, either directly
+         or through a Builder.
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the commit failed.
+     */
+    func commit() throws {
+        defer {
+            self.raw = nil
+        }
+        try in_progress_commit(try self.validPointer()).pointee.tryUnwrap()
+    }
+
+    /**
+     Rolls back all the transacts that have been performed on this `InProgress`, either directly
+     or through a Builder.
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the rollback failed.
+     */
+    func rollback() throws {
+        defer {
+            self.raw = nil
+        }
+        try in_progress_rollback(try self.validPointer()).pointee.tryUnwrap()
+    }
+
+    override func cleanup(pointer: OpaquePointer) {
+        in_progress_destroy(pointer)
+    }
+}

sdks/swift/Mentat/Mentat/Transact/InProgressBuilder.swift

@@ -0,0 +1,372 @@
+/* Copyright 2018 Mozilla
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+ * this file except in compliance with the License. You may obtain a copy of the
+ * License at http://www.apache.org/licenses/LICENSE-2.0
+ * Unless required by applicable law or agreed to in writing, software distributed
+ * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+ * CONDITIONS OF ANY KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations under the License. */
+
+import Foundation
+import MentatStore
+
+/**
+ This class wraps a raw pointer that points to a Rust `InProgressBuilder` object.
+
+ `InProgressBuilder` provides a programmatic interface to performing assertions for entities.
+ It provides functions for adding and retracting values for attributes for an entity within
+ an in progress transaction.
+
+ The `transact` function will transact the assertions that have been added to the `InProgressBuilder`
+ and pass back the `TxReport` that was generated by this transact and the `InProgress` that was
+ used to perform the transact. This enables you to perform further transacts on the same `InProgress`
+ before committing.
+
+ ```
+ let aEntid = txReport.entid(forTempId: "a")
+ let bEntid = txReport.entid(forTempId: "b")
+ do {
+     let builder = try mentat.entityBuilder()
+     try builder.add(entid: bEntid, keyword: ":foo/boolean", boolean: true)
+     try builder.add(entid: aEntid, keyword: ":foo/instant", date: newDate)
+     let (inProgress, report) = try builder.transact()
+     try inProgress.transact(transaction: "[[:db/add \(aEntid) :foo/long 22]]")
+     try inProgress.commit()
+     ...
+ } catch {
+    ...
+ }
+ ```
+
+ The `commit` function will transact and commit the assertions that have been added to the `EntityBuilder`.
+ It will consume the `InProgress` used to perform the transact. It returns the `TxReport` generated by
+ the transact. After calling `commit`, a new transaction must be started by calling `Mentat.beginTransaction()`
+ in order to perform further actions.
+
+ ```
+ let aEntid = txReport.entid(forTempId: "a")
+ let bEntid = txReport.entid(forTempId: "b")
+ do {
+     let builder = try mentat.entityBuilder(forEntid: aEntid)
+     try builder.add(entid: bEntid, keyword: ":foo/boolean", boolean: true)
+     try builder.add(entid: aEntid, keyword: ":foo/instant", date: newDate)
+     let report = try builder.commit()
+    ...
+ } catch {
+    ...
+ }
+ ```
+ */
+class InProgressBuilder: OptionalRustObject {
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/long`.
+     */
+    func add(entid: Entid, keyword: String, long value: Int64) throws {
+        try in_progress_builder_add_long(try self.validPointer(), entid, keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/ref`.
+     */
+    func add(entid: Entid, keyword: String, reference value: Entid) throws {
+        try in_progress_builder_add_ref(try self.validPointer(), entid, keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/keyword`.
+     */
+    func add(entid: Entid, keyword: String, keyword value: String) throws {
+        try in_progress_builder_add_keyword(try self.validPointer(), entid, keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/boolean`.
+     */
+    func add(entid: Entid, keyword: String, boolean value: Bool) throws {
+        try in_progress_builder_add_boolean(try self.validPointer(), entid, keyword, value ? 1 : 0).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/double`.
+     */
+    func add(entid: Entid, keyword: String, double value: Double) throws {
+        try in_progress_builder_add_double(try self.validPointer(), entid, keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/instant`.
+     */
+    func add(entid: Entid, keyword: String, date value: Date) throws {
+        try in_progress_builder_add_timestamp(try self.validPointer(), entid, keyword, value.toMicroseconds()).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/string`.
+     */
+    func add(entid: Entid, keyword: String, string value: String) throws {
+        try in_progress_builder_add_string(try self.validPointer(), entid, keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Asserts the value of attribute `keyword` to be the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be asserted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/uuid`.
+     */
+    func add(entid: Entid, keyword: String, uuid value: UUID) throws {
+        var rawUuid = value.uuid
+        let _ = try withUnsafePointer(to: &rawUuid) { uuidPtr in
+            try in_progress_builder_add_uuid(try self.validPointer(), entid, keyword, uuidPtr).pointee.tryUnwrap()
+        }
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/long`.
+     */
+    func retract(entid: Entid, keyword: String, long value: Int64) throws {
+        try in_progress_builder_retract_long(try self.validPointer(), entid, keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/ref`.
+     */
+    func retract(entid: Entid, keyword: String, reference value: Entid) throws {
+        try in_progress_builder_retract_ref(try self.validPointer(), entid, keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/keyword`.
+     */
+    func retract(entid: Entid, keyword: String, keyword value: String) throws {
+        try in_progress_builder_retract_keyword(try self.validPointer(), entid, keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/boolean`.
+     */
+    func retract(entid: Entid, keyword: String, boolean value: Bool) throws {
+        try in_progress_builder_retract_boolean(try self.validPointer(), entid, keyword, value ? 1 : 0).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/double`.
+     */
+    func retract(entid: Entid, keyword: String, double value: Double) throws {
+        try in_progress_builder_retract_double(try self.validPointer(), entid, keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/instant`.
+     */
+    func retract(entid: Entid, keyword: String, date value: Date) throws {
+        try in_progress_builder_retract_timestamp(try self.validPointer(), entid, keyword, value.toMicroseconds()).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/string`.
+     */
+    func retract(entid: Entid, keyword: String, string value: String) throws {
+        try in_progress_builder_retract_string(try self.validPointer(), entid, keyword, value).pointee.tryUnwrap()
+    }
+
+    /**
+     Retracts the value of attribute `keyword` from the provided `value` for entity `entid`.
+
+     - Parameter entid: The `Entid` of the entity to be touched.
+     - Parameter keyword: The name of the attribute in the format `:namespace/name`.
+     - Parameter value: The value to be retracted
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if the attribute is not present in the schema or the attribute value type
+     is not `:db.type/uuid`.
+     */
+    func retract(entid: Entid, keyword: String, uuid value: UUID) throws {
+        var rawUuid = value.uuid
+        let _ = try withUnsafePointer(to: &rawUuid) { uuidPtr in
+            try in_progress_builder_retract_uuid(try self.validPointer(), entid, keyword, uuidPtr).pointee.tryUnwrap()
+        }
+    }
+
+    /**
+     Transacts the added assertions. This consumes the pointer associated with this `InProgressBuilder`
+     such that no further assertions can be added after the `transact` has completed. To perform
+     further assertions, use the `InProgress` returned from this function.
+
+     This does not commit the transaction. In order to do so, `commit` can be called on the `InProgress` returned
+     from this function.
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if an error occured during the execution of the transact.
+
+     - Returns: The current `InProgress` and the `TxReport` generated by the transact.
+     */
+    func transact() throws -> (InProgress, TxReport?) {
+        defer {
+            self.raw = nil
+        }
+        let result = in_progress_builder_transact(try self.validPointer()).pointee
+        let inProgress = InProgress(raw: result.inProgress)
+        guard let report = try result.result.pointee.tryUnwrap() else {
+            return (inProgress, nil)
+        }
+        return (inProgress, TxReport(raw: report))
+    }
+
+    /**
+     Transacts the added assertions and commits. This consumes the pointer associated with this `InProgressBuilder`
+     and the associated `InProgress` such that no further assertions can be added after the `commit` has completed.
+     To perform further assertions, a new `InProgress` or `InProgressBuilder` should be created.
+
+     - Throws: `PointerError.pointerConsumed` if the underlying raw pointer has already consumed, which will occur if the builder
+     has already been transacted or committed.
+     - Throws: `ResultError.error` if an error occured during the execution of the transact.
+
+     - Returns: The `TxReport` generated by the transact.
+     */
+    func commit() throws -> TxReport {
+        defer {
+            self.raw = nil
+        }
+        return TxReport(raw: try in_progress_builder_commit(try self.validPointer()).pointee.unwrap())
+    }
+
+    override func cleanup(pointer: OpaquePointer) {
+        in_progress_builder_destroy(pointer)
+    }
+}

sdks/swift/Mentat/Mentat/Transact/TxReport.swift

@@ -13,7 +13,7 @@ import Foundation
 import MentatStore
 
 /**
- This class wraps a raw pointer than points to a Rust `TxReport` object.
+ This class wraps a raw pointer that points to a Rust `TxReport` object.
 
  The `TxReport` contains information about a successful Mentat transaction.
 

sdks/swift/Mentat/Mentat/store.h

@@ -60,6 +60,16 @@ struct Option {
 };
 typedef struct Option Option;
 
+/*
+ A mapping of the InProgressTransactResult repr(C) Rust object.
+ The memory for this is managed by Swift.
+ */
+struct InProgressTransactResult {
+    struct InProgress*_Nonnull inProgress;
+    struct Result*_Nonnull result;
+};
+typedef struct InProgressTransactResult InProgressTransactResult;
+
 /*
  A Mapping for the ValueType Rust object.
  */
@@ -100,13 +110,72 @@ void typed_value_list_destroy(struct QueryResultRow* _Nullable obj);
 void typed_value_list_iter_destroy(struct QueryRowIterator* _Nullable obj);
 void typed_value_result_set_destroy(struct QueryResultRows* _Nullable obj);
 void typed_value_result_set_iter_destroy(struct QueryRowsIterator* _Nullable obj);
+void in_progress_destroy(struct InProgress* _Nullable obj);
+void in_progress_builder_destroy(struct InProgressBuilder* _Nullable obj);
+void entity_builder_destroy(struct EntityBuilder* _Nullable obj);
+
+// caching
+struct Result*_Nonnull  store_cache_attribute_forward(struct Store*_Nonnull store, const char* _Nonnull attribute);
+struct Result*_Nonnull  store_cache_attribute_reverse(struct Store*_Nonnull store, const char* _Nonnull attribute);
+struct Result*_Nonnull  store_cache_attribute_bi_directional(struct Store*_Nonnull store, const char* _Nonnull attribute);
 
 // transact
 struct Result*_Nonnull store_transact(struct Store*_Nonnull store, const char* _Nonnull transaction);
 const int64_t* _Nullable tx_report_entity_for_temp_id(const struct TxReport* _Nonnull report, const char* _Nonnull tempid);
 int64_t tx_report_get_entid(const struct TxReport* _Nonnull report);
 int64_t tx_report_get_tx_instant(const struct TxReport* _Nonnull report);
+struct Result*_Nonnull store_begin_transaction(struct Store*_Nonnull store);
 
+// in progress
+struct Result*_Nonnull in_progress_transact(struct InProgress*_Nonnull in_progress, const char* _Nonnull transaction);
+struct Result*_Nonnull in_progress_commit(struct InProgress*_Nonnull in_progress);
+struct Result*_Nonnull in_progress_rollback(struct InProgress*_Nonnull in_progress);
+
+// in_progress entity building
+struct Result*_Nonnull store_in_progress_builder(struct Store*_Nonnull store);
+struct InProgressBuilder*_Nonnull in_progress_builder(struct InProgress*_Nonnull in_progress);
+struct EntityBuilder*_Nonnull in_progress_entity_builder_from_temp_id(struct InProgress*_Nonnull in_progress, const char*_Nonnull temp_id);
+struct EntityBuilder*_Nonnull in_progress_entity_builder_from_entid(struct InProgress*_Nonnull in_progress, const int64_t entid);
+struct Result*_Nonnull in_progress_builder_add_string(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const char*_Nonnull value);
+struct Result*_Nonnull in_progress_builder_add_long(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull in_progress_builder_add_ref(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull in_progress_builder_add_keyword(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const char*_Nonnull value);
+struct Result*_Nonnull in_progress_builder_add_timestamp(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull in_progress_builder_add_boolean(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const int32_t value);
+struct Result*_Nonnull in_progress_builder_add_double(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const double value);
+struct Result*_Nonnull in_progress_builder_add_uuid(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const uuid_t* _Nonnull value);
+struct Result*_Nonnull in_progress_builder_retract_string(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const char*_Nonnull value);
+struct Result*_Nonnull in_progress_builder_retract_long(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull in_progress_builder_retract_ref(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull in_progress_builder_retract_keyword(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const char*_Nonnull value);
+struct Result*_Nonnull in_progress_builder_retract_timestamp(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull in_progress_builder_retract_boolean(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const int32_t value);
+struct Result*_Nonnull in_progress_builder_retract_double(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const double value);
+struct Result*_Nonnull in_progress_builder_retract_uuid(struct InProgressBuilder*_Nonnull builder, const int64_t entid, const char*_Nonnull kw, const uuid_t* _Nonnull value);
+struct InProgressTransactResult*_Nonnull in_progress_builder_transact(struct InProgressBuilder*_Nonnull builder);
+struct Result*_Nonnull in_progress_builder_commit(struct InProgressBuilder*_Nonnull builder);
+
+// entity building
+struct Result*_Nonnull store_entity_builder_from_temp_id(struct Store*_Nonnull store, const char*_Nonnull temp_id);
+struct Result*_Nonnull store_entity_builder_from_entid(struct Store*_Nonnull store, const int64_t entid);
+struct Result*_Nonnull entity_builder_add_string(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const char*_Nonnull value);
+struct Result*_Nonnull entity_builder_add_long(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull entity_builder_add_ref(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull entity_builder_add_keyword(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const char*_Nonnull value);
+struct Result*_Nonnull entity_builder_add_boolean(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const int32_t value);
+struct Result*_Nonnull entity_builder_add_double(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const double value);
+struct Result*_Nonnull entity_builder_add_timestamp(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull entity_builder_add_uuid(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const uuid_t* _Nonnull value);
+struct Result*_Nonnull entity_builder_retract_string(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const char*_Nonnull value);
+struct Result*_Nonnull entity_builder_retract_long(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull entity_builder_retract_ref(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull entity_builder_retract_keyword(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const char*_Nonnull value);
+struct Result*_Nonnull entity_builder_retract_boolean(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const int32_t value);
+struct Result*_Nonnull entity_builder_retract_double(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const double value);
+struct Result*_Nonnull entity_builder_retract_timestamp(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const int64_t value);
+struct Result*_Nonnull entity_builder_retract_uuid(struct EntityBuilder*_Nonnull builder, const char*_Nonnull kw, const uuid_t* _Nonnull value);
+struct InProgressTransactResult*_Nonnull entity_builder_transact(struct InProgressBuilder*_Nonnull builder);
+struct Result*_Nonnull entity_builder_commit(struct EntityBuilder*_Nonnull builder);
 
 // Sync
 struct Result*_Nonnull store_sync(struct Store*_Nonnull store, const char* _Nonnull user_uuid, const char* _Nonnull server_uri);

sdks/swift/Mentat/MentatTests/MentatTests.swift

@@ -120,7 +120,8 @@ class MentatTests: XCTestCase {
                 [:db/add "u" :db/cardinality :db.cardinality/one]
             ]
             """
-            let report = try mentat.transact(transaction: schema)
+            let transaction = try mentat.beginTransaction();
+            let report = try transaction.transact(transaction: schema)
             let stringEntid = report.entid(forTempId: "s")!
 
             let data = """
@@ -142,7 +143,8 @@ class MentatTests: XCTestCase {
                 [:db/add "b" :foo/uuid #uuid "4cb3f828-752d-497a-90c9-b1fd516d5644"]
             ]
             """
-            let dataReport = try mentat.transact(transaction: data)
+            let dataReport = try transaction.transact(transaction: data)
+            try transaction.commit();
             return (report, dataReport)
         } catch {
             assertionFailure(error.localizedDescription)
@@ -760,6 +762,483 @@ class MentatTests: XCTestCase {
         }
     }
 
+    func test3InProgressTransact() {
+        let mentat = Mentat()
+        let (_, report) = self.populateWithTypesSchema(mentat: mentat)
+        XCTAssertNotNil(report)
+    }
+
+    func testInProgressRollback() {
+        let mentat = Mentat()
+        let (_, report) = self.populateWithTypesSchema(mentat: mentat)
+        XCTAssertNotNil(report)
+        let aEntid = report!.entid(forTempId: "a")!
+
+        let preLongValue = try! mentat.value(forAttribute: ":foo/long", ofEntity: aEntid)
+        XCTAssertEqual(25, preLongValue?.asLong())
+
+        let inProgress = try! mentat.beginTransaction()
+        XCTAssertNoThrow(try inProgress.transact(transaction: "[[:db/add \(aEntid) :foo/long 22]]"))
+        XCTAssertNoThrow(try inProgress.rollback())
+
+        let postLongValue = try! mentat.value(forAttribute: ":foo/long", ofEntity: aEntid)
+        XCTAssertEqual(25, postLongValue?.asLong())
+
+    }
+
+    func testInProgressEntityBuilder() {
+        let mentat = Mentat()
+        let (schemaReport, dataReport) = self.populateWithTypesSchema(mentat: mentat)
+        let bEntid = dataReport!.entid(forTempId: "b")!
+        let longEntid = schemaReport!.entid(forTempId: "l")!
+        let stringEntid = schemaReport!.entid(forTempId: "s")!
+        // test that the values are as expected
+        let query = """
+                    [:find [?b ?i ?u ?l ?d ?s ?k ?r]
+                     :in ?e
+                     :where [?e :foo/boolean ?b]
+                            [?e :foo/instant ?i]
+                            [?e :foo/uuid ?u]
+                            [?e :foo/long ?l]
+                            [?e :foo/double ?d]
+                            [?e :foo/string ?s]
+                            [?e :foo/keyword ?k]
+                            [?e :foo/ref ?r]]
+                    """
+        let formatter = DateFormatter()
+        formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
+        XCTAssertNoThrow(try mentat.query(query: query).bind(varName: "?e", toReference: bEntid).runTuple { (result) in
+            XCTAssertNotNil(result)
+            XCTAssertEqual(false, result?.asBool(index: 0))
+
+            let previousDate = formatter.date(from: "2018-01-01T11:00:00+00:00")
+            XCTAssertEqual(previousDate, result?.asDate(index: 1))
+
+            let previousUuid = UUID(uuidString: "4cb3f828-752d-497a-90c9-b1fd516d5644")!
+            XCTAssertEqual(previousUuid, result?.asUUID(index: 2))
+
+            XCTAssertEqual(50, result?.asLong(index: 3))
+            XCTAssertEqual(22.46, result?.asDouble(index: 4))
+            XCTAssertEqual("Silence is worse; all truths that are kept silent become poisonous.", result?.asString(index: 5))
+            XCTAssertEqual(":foo/string", result?.asKeyword(index: 6))
+            XCTAssertEqual(stringEntid, result?.asEntid(index: 7))
+        })
+
+        let builder = try! mentat.entityBuilder()
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/boolean", boolean: true))
+        let newDate = Date()
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/instant", date: newDate))
+        let newUUID = UUID()
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/uuid", uuid: newUUID))
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/long", long: 75))
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/double", double: 81.3))
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/string", string: "Become who you are!"))
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/keyword", keyword: ":foo/long"))
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/ref", reference: longEntid))
+        XCTAssertNoThrow(try builder.commit())
+
+        // test that the values have changed
+        XCTAssertNoThrow(try mentat.query(query: query).bind(varName: "?e", toReference: bEntid).runTuple { (result) in
+            XCTAssertNotNil(result)
+            XCTAssertEqual(true, result?.asBool(index: 0))
+            XCTAssertEqual(formatter.string(from: newDate), formatter.string(from: result!.asDate(index: 1)))
+            XCTAssertEqual(newUUID, result?.asUUID(index: 2))
+            XCTAssertEqual(75, result?.asLong(index: 3))
+            XCTAssertEqual(81.3, result?.asDouble(index: 4))
+            XCTAssertEqual("Become who you are!", result?.asString(index: 5))
+            XCTAssertEqual(":foo/long", result?.asKeyword(index: 6))
+            XCTAssertEqual(longEntid, result?.asEntid(index: 7))
+       })
+    }
+
+    func testEntityBuilderForEntid() {
+        let mentat = Mentat()
+        let (schemaReport, dataReport) = self.populateWithTypesSchema(mentat: mentat)
+        let bEntid = dataReport!.entid(forTempId: "b")!
+        let longEntid = schemaReport!.entid(forTempId: "l")!
+        let stringEntid = schemaReport!.entid(forTempId: "s")!
+        // test that the values are as expected
+        let query = """
+                    [:find [?b ?i ?u ?l ?d ?s ?k ?r]
+                     :in ?e
+                     :where [?e :foo/boolean ?b]
+                            [?e :foo/instant ?i]
+                            [?e :foo/uuid ?u]
+                            [?e :foo/long ?l]
+                            [?e :foo/double ?d]
+                            [?e :foo/string ?s]
+                            [?e :foo/keyword ?k]
+                            [?e :foo/ref ?r]]
+                    """
+        let formatter = DateFormatter()
+        formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
+        XCTAssertNoThrow(try mentat.query(query: query).bind(varName: "?e", toReference: bEntid).runTuple { (result) in
+            XCTAssertNotNil(result)
+            XCTAssertEqual(false, result?.asBool(index: 0))
+
+            let previousDate = formatter.date(from: "2018-01-01T11:00:00+00:00")
+            XCTAssertEqual(previousDate, result?.asDate(index: 1))
+
+            let previousUuid = UUID(uuidString: "4cb3f828-752d-497a-90c9-b1fd516d5644")!
+            XCTAssertEqual(previousUuid, result?.asUUID(index: 2))
+
+            XCTAssertEqual(50, result?.asLong(index: 3))
+            XCTAssertEqual(22.46, result?.asDouble(index: 4))
+            XCTAssertEqual("Silence is worse; all truths that are kept silent become poisonous.", result?.asString(index: 5))
+            XCTAssertEqual(":foo/string", result?.asKeyword(index: 6))
+            XCTAssertEqual(stringEntid, result?.asEntid(index: 7))
+        })
+
+        let builder = try! mentat.entityBuilder(forEntid: bEntid)
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/boolean", boolean: true))
+        let newDate = Date()
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/instant", date: newDate))
+        let newUUID = UUID()
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/uuid", uuid: newUUID))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/long", long: 75))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/double", double: 81.3))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/string", string: "Become who you are!"))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/keyword", keyword: ":foo/long"))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/ref", reference: longEntid))
+        XCTAssertNoThrow(try builder.commit())
+
+        // test that the values have changed
+        XCTAssertNoThrow(try mentat.query(query: query).bind(varName: "?e", toReference: bEntid).runTuple { (result) in
+            XCTAssertNotNil(result)
+            XCTAssertEqual(true, result?.asBool(index: 0))
+            XCTAssertEqual(formatter.string(from: newDate), formatter.string(from: result!.asDate(index: 1)))
+            XCTAssertEqual(newUUID, result?.asUUID(index: 2))
+            XCTAssertEqual(75, result?.asLong(index: 3))
+            XCTAssertEqual(81.3, result?.asDouble(index: 4))
+            XCTAssertEqual("Become who you are!", result?.asString(index: 5))
+            XCTAssertEqual(":foo/long", result?.asKeyword(index: 6))
+            XCTAssertEqual(longEntid, result?.asEntid(index: 7))
+        })
+    }
+
+    func testEntityBuilderForTempid() {
+        let mentat = Mentat()
+        let (schemaReport, _) = self.populateWithTypesSchema(mentat: mentat)
+        let longEntid = schemaReport!.entid(forTempId: "l")!
+        // test that the values are as expected
+        let query = """
+                    [:find [?b ?i ?u ?l ?d ?s ?k ?r]
+                     :in ?e
+                     :where [?e :foo/boolean ?b]
+                            [?e :foo/instant ?i]
+                            [?e :foo/uuid ?u]
+                            [?e :foo/long ?l]
+                            [?e :foo/double ?d]
+                            [?e :foo/string ?s]
+                            [?e :foo/keyword ?k]
+                            [?e :foo/ref ?r]]
+                    """
+        let formatter = DateFormatter()
+        formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
+
+        let builder = try! mentat.entityBuilder(forTempId: "c")
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/boolean", boolean: true))
+        let newDate = Date()
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/instant", date: newDate))
+        let newUUID = UUID()
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/uuid", uuid: newUUID))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/long", long: 75))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/double", double: 81.3))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/string", string: "Become who you are!"))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/keyword", keyword: ":foo/long"))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/ref", reference: longEntid))
+        let report = try! builder.commit()
+        let cEntid = report.entid(forTempId: "c")!
+        // test that the values have changed
+        XCTAssertNoThrow(try mentat.query(query: query).bind(varName: "?e", toReference: cEntid).runTuple { (result) in
+            XCTAssertNotNil(result)
+            XCTAssertEqual(true, result?.asBool(index: 0))
+            XCTAssertEqual(formatter.string(from: newDate), formatter.string(from: result!.asDate(index: 1)))
+            XCTAssertEqual(newUUID, result?.asUUID(index: 2))
+            XCTAssertEqual(75, result?.asLong(index: 3))
+            XCTAssertEqual(81.3, result?.asDouble(index: 4))
+            XCTAssertEqual("Become who you are!", result?.asString(index: 5))
+            XCTAssertEqual(":foo/long", result?.asKeyword(index: 6))
+            XCTAssertEqual(longEntid, result?.asEntid(index: 7))
+        })
+    }
+
+    func testInProgressBuilderTransact() {
+        let mentat = Mentat()
+        let (schemaReport, dataReport) = self.populateWithTypesSchema(mentat: mentat)
+        let aEntid = dataReport!.entid(forTempId: "a")!
+        let bEntid = dataReport!.entid(forTempId: "b")!
+        let longEntid = schemaReport!.entid(forTempId: "l")!
+        // test that the values are as expected
+        let query = """
+                    [:find [?b ?i ?u ?l ?d ?s ?k ?r]
+                     :in ?e
+                     :where [?e :foo/boolean ?b]
+                            [?e :foo/instant ?i]
+                            [?e :foo/uuid ?u]
+                            [?e :foo/long ?l]
+                            [?e :foo/double ?d]
+                            [?e :foo/string ?s]
+                            [?e :foo/keyword ?k]
+                            [?e :foo/ref ?r]]
+                    """
+        let formatter = DateFormatter()
+        formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
+
+        let builder = try! mentat.entityBuilder()
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/boolean", boolean: true))
+        let newDate = Date()
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/instant", date: newDate))
+        let newUUID = UUID()
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/uuid", uuid: newUUID))
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/long", long: 75))
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/double", double: 81.3))
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/string", string: "Become who you are!"))
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/keyword", keyword: ":foo/long"))
+        XCTAssertNoThrow(try builder.add(entid: bEntid, keyword: ":foo/ref", reference: longEntid))
+        let (inProgress, report) = try! builder.transact()
+        XCTAssertNotNil(inProgress)
+        XCTAssertNotNil(report)
+        XCTAssertNoThrow(try inProgress.transact(transaction: "[[:db/add \(aEntid) :foo/long 22]]"))
+        XCTAssertNoThrow(try inProgress.commit())
+
+        // test that the values have changed
+        XCTAssertNoThrow(try mentat.query(query: query).bind(varName: "?e", toReference: bEntid).runTuple { (result) in
+            XCTAssertNotNil(result)
+            XCTAssertEqual(true, result?.asBool(index: 0))
+            XCTAssertEqual(formatter.string(from: newDate), formatter.string(from: result!.asDate(index: 1)))
+            XCTAssertEqual(newUUID, result?.asUUID(index: 2))
+            XCTAssertEqual(75, result?.asLong(index: 3))
+            XCTAssertEqual(81.3, result?.asDouble(index: 4))
+            XCTAssertEqual("Become who you are!", result?.asString(index: 5))
+            XCTAssertEqual(":foo/long", result?.asKeyword(index: 6))
+            XCTAssertEqual(longEntid, result?.asEntid(index: 7))
+        })
+
+        let longValue = try! mentat.value(forAttribute: ":foo/long", ofEntity: aEntid)
+        XCTAssertEqual(22, longValue?.asLong())
+    }
+
+    func testEntityBuilderTransact() {
+        let mentat = Mentat()
+        let (schemaReport, dataReport) = self.populateWithTypesSchema(mentat: mentat)
+        let aEntid = dataReport!.entid(forTempId: "a")!
+        let bEntid = dataReport!.entid(forTempId: "b")!
+        let longEntid = schemaReport!.entid(forTempId: "l")!
+        // test that the values are as expected
+        let query = """
+                    [:find [?b ?i ?u ?l ?d ?s ?k ?r]
+                     :in ?e
+                     :where [?e :foo/boolean ?b]
+                            [?e :foo/instant ?i]
+                            [?e :foo/uuid ?u]
+                            [?e :foo/long ?l]
+                            [?e :foo/double ?d]
+                            [?e :foo/string ?s]
+                            [?e :foo/keyword ?k]
+                            [?e :foo/ref ?r]]
+                    """
+        let formatter = DateFormatter()
+        formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
+
+        let builder = try! mentat.entityBuilder(forEntid: bEntid)
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/boolean", boolean: true))
+        let newDate = Date()
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/instant", date: newDate))
+        let newUUID = UUID()
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/uuid", uuid: newUUID))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/long", long: 75))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/double", double: 81.3))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/string", string: "Become who you are!"))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/keyword", keyword: ":foo/long"))
+        XCTAssertNoThrow(try builder.add(keyword: ":foo/ref", reference: longEntid))
+        let (inProgress, report) = try! builder.transact()
+        XCTAssertNotNil(inProgress)
+        XCTAssertNotNil(report)
+        XCTAssertNoThrow(try inProgress.transact(transaction: "[[:db/add \(aEntid) :foo/long 22]]"))
+        XCTAssertNoThrow(try inProgress.commit())
+
+        // test that the values have changed
+        XCTAssertNoThrow(try mentat.query(query: query).bind(varName: "?e", toReference: bEntid).runTuple { (result) in
+            XCTAssertNotNil(result)
+            XCTAssertEqual(true, result?.asBool(index: 0))
+            XCTAssertEqual(formatter.string(from: newDate), formatter.string(from: result!.asDate(index: 1)))
+            XCTAssertEqual(newUUID, result?.asUUID(index: 2))
+            XCTAssertEqual(75, result?.asLong(index: 3))
+            XCTAssertEqual(81.3, result?.asDouble(index: 4))
+            XCTAssertEqual("Become who you are!", result?.asString(index: 5))
+            XCTAssertEqual(":foo/long", result?.asKeyword(index: 6))
+            XCTAssertEqual(longEntid, result?.asEntid(index: 7))
+        })
+
+        let longValue = try! mentat.value(forAttribute: ":foo/long", ofEntity: aEntid)
+        XCTAssertEqual(22, longValue?.asLong())
+    }
+
+    func testEntityBuilderRetract() {
+        let mentat = Mentat()
+        let (schemaReport, dataReport) = self.populateWithTypesSchema(mentat: mentat)
+        let bEntid = dataReport!.entid(forTempId: "b")!
+        let stringEntid = schemaReport!.entid(forTempId: "s")!
+        // test that the values are as expected
+        let query = """
+                    [:find [?b ?i ?u ?l ?d ?s ?k ?r]
+                     :in ?e
+                     :where [?e :foo/boolean ?b]
+                            [?e :foo/instant ?i]
+                            [?e :foo/uuid ?u]
+                            [?e :foo/long ?l]
+                            [?e :foo/double ?d]
+                            [?e :foo/string ?s]
+                            [?e :foo/keyword ?k]
+                            [?e :foo/ref ?r]]
+                    """
+        let formatter = DateFormatter()
+        formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
+        let previousDate = formatter.date(from: "2018-01-01T11:00:00+00:00")!
+        let previousUuid = UUID(uuidString: "4cb3f828-752d-497a-90c9-b1fd516d5644")!
+        XCTAssertNoThrow(try mentat.query(query: query).bind(varName: "?e", toReference: bEntid).runTuple { (result) in
+            XCTAssertNotNil(result)
+            XCTAssertEqual(false, result?.asBool(index: 0))
+            XCTAssertEqual(previousDate, result?.asDate(index: 1))
+            XCTAssertEqual(previousUuid, result?.asUUID(index: 2))
+            XCTAssertEqual(50, result?.asLong(index: 3))
+            XCTAssertEqual(22.46, result?.asDouble(index: 4))
+            XCTAssertEqual("Silence is worse; all truths that are kept silent become poisonous.", result?.asString(index: 5))
+            XCTAssertEqual(":foo/string", result?.asKeyword(index: 6))
+            XCTAssertEqual(stringEntid, result?.asEntid(index: 7))
+        })
+
+        let builder = try! mentat.entityBuilder(forEntid: bEntid)
+        XCTAssertNoThrow(try builder.retract(keyword: ":foo/boolean", boolean: false))
+        XCTAssertNoThrow(try builder.retract(keyword: ":foo/instant", date: previousDate))
+        XCTAssertNoThrow(try builder.retract(keyword: ":foo/uuid", uuid: previousUuid))
+        XCTAssertNoThrow(try builder.retract(keyword: ":foo/long", long: 50))
+        XCTAssertNoThrow(try builder.retract(keyword: ":foo/double", double: 22.46))
+        XCTAssertNoThrow(try builder.retract(keyword: ":foo/string", string: "Silence is worse; all truths that are kept silent become poisonous."))
+        XCTAssertNoThrow(try builder.retract(keyword: ":foo/keyword", keyword: ":foo/string"))
+        XCTAssertNoThrow(try builder.retract(keyword: ":foo/ref", reference: stringEntid))
+        XCTAssertNoThrow(try builder.commit())
+
+        XCTAssertNoThrow(try mentat.query(query: query).bind(varName: "?e", toReference: bEntid).runTuple { (result) in
+            XCTAssertNil(result)
+        })
+    }
+
+    func testInProgressEntityBuilderRetract() {
+        let mentat = Mentat()
+        let (schemaReport, dataReport) = self.populateWithTypesSchema(mentat: mentat)
+        let bEntid = dataReport!.entid(forTempId: "b")!
+        let stringEntid = schemaReport!.entid(forTempId: "s")!
+        // test that the values are as expected
+        let query = """
+                    [:find [?b ?i ?u ?l ?d ?s ?k ?r]
+                     :in ?e
+                     :where [?e :foo/boolean ?b]
+                            [?e :foo/instant ?i]
+                            [?e :foo/uuid ?u]
+                            [?e :foo/long ?l]
+                            [?e :foo/double ?d]
+                            [?e :foo/string ?s]
+                            [?e :foo/keyword ?k]
+                            [?e :foo/ref ?r]]
+                    """
+        let formatter = DateFormatter()
+        formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
+        let previousDate = formatter.date(from: "2018-01-01T11:00:00+00:00")!
+        let previousUuid = UUID(uuidString: "4cb3f828-752d-497a-90c9-b1fd516d5644")!
+        XCTAssertNoThrow(try mentat.query(query: query).bind(varName: "?e", toReference: bEntid).runTuple { (result) in
+            XCTAssertNotNil(result)
+            XCTAssertEqual(false, result?.asBool(index: 0))
+            XCTAssertEqual(previousDate, result?.asDate(index: 1))
+            XCTAssertEqual(previousUuid, result?.asUUID(index: 2))
+            XCTAssertEqual(50, result?.asLong(index: 3))
+            XCTAssertEqual(22.46, result?.asDouble(index: 4))
+            XCTAssertEqual("Silence is worse; all truths that are kept silent become poisonous.", result?.asString(index: 5))
+            XCTAssertEqual(":foo/string", result?.asKeyword(index: 6))
+            XCTAssertEqual(stringEntid, result?.asEntid(index: 7))
+        })
+
+        let builder = try! mentat.entityBuilder()
+        XCTAssertNoThrow(try builder.retract(entid: bEntid, keyword: ":foo/boolean", boolean: false))
+        XCTAssertNoThrow(try builder.retract(entid: bEntid, keyword: ":foo/instant", date: previousDate))
+        XCTAssertNoThrow(try builder.retract(entid: bEntid, keyword: ":foo/uuid", uuid: previousUuid))
+        XCTAssertNoThrow(try builder.retract(entid: bEntid, keyword: ":foo/long", long: 50))
+        XCTAssertNoThrow(try builder.retract(entid: bEntid, keyword: ":foo/double", double: 22.46))
+        XCTAssertNoThrow(try builder.retract(entid: bEntid, keyword: ":foo/string", string: "Silence is worse; all truths that are kept silent become poisonous."))
+        XCTAssertNoThrow(try builder.retract(entid: bEntid, keyword: ":foo/keyword", keyword: ":foo/string"))
+        XCTAssertNoThrow(try builder.retract(entid: bEntid, keyword: ":foo/ref", reference: stringEntid))
+        XCTAssertNoThrow(try builder.commit())
+
+        XCTAssertNoThrow(try mentat.query(query: query).bind(varName: "?e", toReference: bEntid).runTuple { (result) in
+            XCTAssertNil(result)
+        })
+    }
+
+    func testCaching() {
+        let query = """
+                [:find ?district :where
+                [?neighborhood :neighborhood/name \"Beacon Hill\"]
+                [?neighborhood :neighborhood/district ?d]
+                [?d :district/name ?district]]
+                """
+
+        let mentat = openAndInitializeCitiesStore()
+
+        struct QueryTimer {
+            private var _start: UInt64
+            private var _end: UInt64
+
+            init() {
+                self._start = 0
+                self._end = 0
+            }
+
+            private func currentTimeNanos() -> UInt64 {
+                var info = mach_timebase_info()
+                guard mach_timebase_info(&info) == KERN_SUCCESS else { return 0 }
+                let currentTime = mach_absolute_time()
+                return currentTime * UInt64(info.numer) / UInt64(info.denom)
+            }
+
+
+            mutating func start() {
+                self._start = self.currentTimeNanos()
+            }
+
+            mutating func end() {
+                self._end = self.currentTimeNanos()
+            }
+
+            func duration() -> UInt64 {
+                return self._end - self._start
+            }
+        }
+
+        var uncachedTimer = QueryTimer()
+        uncachedTimer.start()
+
+        XCTAssertNoThrow(try mentat.query(query: query).run { (result) in
+            uncachedTimer.end()
+            XCTAssertNotNil(result)
+        })
+
+        XCTAssertNoThrow(try mentat.cache(attribute: ":neighborhood/name", direction: CacheDirection.reverse))
+        XCTAssertNoThrow(try mentat.cache(attribute: ":neighborhood/district", direction: CacheDirection.forward))
+
+        var cachedTimer = QueryTimer()
+        cachedTimer.start()
+
+        XCTAssertNoThrow(try mentat.query(query: query).run { (result) in
+            cachedTimer.end()
+            XCTAssertNotNil(result)
+        })
+
+        let timingDifference = uncachedTimer.duration() - cachedTimer.duration()
+        print("Cached query is \(timingDifference) nanoseconds faster than the uncached query")
+
+        XCTAssertLessThan(cachedTimer.duration(), uncachedTimer.duration())
+    }
 
     // TODO: Add tests for transaction observation
 }