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0.3.0

Architectural rewrite. The 0.x line is not backwards-compatible with 0.2.0.

Feature surface (parity with 0.2.0)

  • Child workflows. API.execute_child_workflow/3 starts a child and blocks until it completes. Start failure, child failure, and child cancellation each surface as a structured Temporalex.ChildWorkflowFailure wrapping the underlying cause.
  • API.signal_child_workflow/4. Send a durable signal to a child workflow by id. Blocks until Temporal confirms delivery (or fails). Works from inside run/1, parallel branches, sync handlers, and async update handlers.

Bug fix in this release

  • Activation-time update race. Updates arriving in the same activation as InitializeWorkflow (replay scenarios after a cache eviction) were being rejected with {:not_accepting_update, _} before the workflow runner had a chance to enter its phase. Fixed by processing activation jobs in two phases — input jobs (initialize, resolutions) first, drain scheduler to drain workflow code to its parked state, then message jobs (signals, updates, queries). Caught by the update_workflow integration test, which is now stable across runs.

  • Error unwrap consistency. fail_thread/3 now unwraps internal {:exception, struct, stacktrace} tuples uniformly across all thread kinds — root, parallel branch, phase dispatch, async update handler. Previously only root paths unwrapped, so a workflow that pattern- matched on {:error, %ApplicationError{}} would silently miss failures coming from parallel/1 branches or {:async, _, _} handlers.

Test coverage

160 tests total — 130 unit (against Backend.Test) and 30 live-Temporal integration tests including 6 CLI-driven tests that exercise the external-tooling interop path (temporal workflow start/signal/describe/ cancel/terminate/list).

The core design — deterministic cooperative scheduler, Temporalex.Backend boundary, phase / parallel / scheduler rounds — is authored by @hansihe. See docs/scheduler_and_replay.md and docs/implementation_principles.md for the design source-of-truth.

What changed

  • Deterministic cooperative scheduler. The executor owns thread ordering; BEAM scheduling and mailbox arrival no longer affect command emission order. parallel branches and handler dispatches have stable thread ids and run in deterministic rounds. This eliminates a latent replay correctness gap in 0.2.0 where parallel command order depended on activity timing.
  • Backend boundary. Temporalex.Backend is a behaviour. Two implementations ship: Temporalex.Backend.TemporalCore (Rustler + Temporal Core, production) and Temporalex.Backend.Test (in-memory, deterministic, for unit tests). All Rust / NIF / protobuf details live inside the backend; the executor speaks %Temporalex.Core.Activation{} / %Temporalex.Core.Completion{}.
  • Layer split. Worker (supervisor) → Server (orchestration, backend state, executor registry, activity task supervision) → Executor (deterministic workflow state) → Backend (transport).
  • Internal protocol as structs. Temporalex.Core.{Activation, Job.*, Command.*, Completion, Op.*} replace the tuple-and-keyword-list messages used in 0.2.0. Easier to read, harder to misuse.

Public API changes

  • API.receive/2 → API.phase/2. Same shape (reducer state, signal / update handlers, optional :timeout), better name (receive is a BEAM keyword).
  • Temporalex.Client is handle-based: start_workflow/4 returns a %Client.Handle{}; subsequent operations (signal_workflow, query_workflow, update_workflow, get_result, cancel_workflow, terminate_workflow, describe_workflow) take the handle. update_workflow is now first-class — no more CLI workaround.
  • Workflow execution returns a typed activation transcript. Workflows return {:ok, result} / {:error, reason} / {:continue_as_new, args} — same as 0.2.0.
  • API.side_effect/1 removed. It was knowingly non-durable across cache evictions in 0.2.0; the design admits primitives only when they have a precise replay contract. Use an activity (or a local activity once re-added — see Known limitations).
  • Worker config. Workers now take a :name and :backend module:
    {Temporalex.Worker,
 name: MyApp.Temporal,
 backend: Temporalex.Backend.TemporalCore,
 target: "http://127.0.0.1:7233",
 namespace: "default",
 task_queue: "checkout",
 workflows: [...],
 activities: [...]}

Restored from 0.2.0

  • Local activities. defactivity foo, local: true do ... end plus API.execute_local_activity/3. Runs the activity body on the worker that scheduled it, with durability via Temporal's history-marker mechanism. Verified end-to-end against a live Temporal server.
  • Structured error types with full proto round-trip: Temporalex.ApplicationError (type, message, non_retryable, details), CancelledError, TimeoutError, ActivityFailure (wraps a cause and carries activity identity), ChildWorkflowFailure, NondeterminismError. Raised in an activity, they reach the workflow as %ActivityFailure{cause: %ApplicationError{...}} with the right fields on the wire and in the Temporal UI.

Known limitations

  • Child workflows. Not yet re-added in 0.3.0. Tracked for 0.3.1 alongside cascading cancel and signal-child surface.

Migration from 0.2.0

0.2.0 was a clean-slate prototype with the same package name. There are no production users we're aware of, so there is no migration path documented. If you were experimenting with 0.2.0, treat 0.3.0 as a fresh start:

  • rename API.receive/2 → API.phase/2
  • remove any API.side_effect/1 calls (use an activity)
  • update worker config to take :name and :backend
  • update client calls to use a handle returned by start_workflow/4

Build & test

  • Tests use Temporalex.Backend.Test and do not require a Temporal server.
  • Integration tests (@moduletag :external) require temporal server start-dev and run via mix test --include external.
  • NIF builds against temporalio/sdk-rust v0.4.0 (was temporalio/sdk-core pinned rev in 0.2.0).

0.2.0

First public release on Hex. Superseded by 0.3.0.

The 0.2.0 surface (API.receive, defactivity ..., local: true, child workflows, Temporalex.Converter, etc.) is preserved in git history at tag v0.2.0 for reference but is no longer maintained. See git log v0.2.0 for the original release notes.