microsoft/bocpy v0.6.0

v0.6.0 - C ABI

Repository: microsoft/bocpy

Tag: v0.6.0

Published: 2026-05-15T19:50:15Z

Prerelease: no

Release notes: Public C ABI for downstream extensions, enabling C-level participation in behavior-oriented concurrency across worker sub-interpreters.

New Features

• Decorator composition with ``@when`` — decorators stacked below

@when are now preserved on the generated behavior function and compose with the behavior body on the worker. Decorators placed above @when raise a SyntaxError at transpile time with actionable guidance. async def functions with @when` are also explicitly rejected.

• Public C ABI (``) — downstream C extensions can

now link against bocpy to register custom Python types as cross-interpreter shareable so :class:Cown can carry instances of them across worker interpreters. The header is C-only, version-gated via the `BOCPY_ABI macro, and bumped on any incompatible change to bocpy.h or xidata.h`. Wheels remain CPython-version-tagged so a runtime ABI mismatch cannot occur.

• `bocpy.get_include()` / `bocpy.get_sources()` — Python-level

helpers that downstream `setup.py` files use to locate the bocpy headers and the small set of C sources that must be compiled into the consuming extension.

• `templates/c_abi_consumer/` — a ready-to-copy template for

building a C extension against the bocpy ABI, including a `setup.py, a probe extension exercising the public surface, and a pytest suite (test_public_c_abi.py`) that validates the ABI end-to-end.

• C source reorganisation — the per-subsystem translation units

introduced in 0.5.0 have been renamed with a `boc_ prefix (boc_compat.[ch], boc_sched.[ch], boc_tags.[ch], boc_terminator.[ch], boc_noticeboard.[ch], boc_cown.h) to give the public ABI a stable, namespaced identity. xidata.h has moved under include/bocpy/ alongside bocpy.h`.

Documentation

• New :doc:c_abi, :doc:messaging, and :doc:noticeboard pages

in the Sphinx site; the API reference has been expanded to cover the public ABI surface.

Breaking Changes

• `noticeboard_version` removed — the global monotonic version

counter introduced in 0.4.0 has been removed. It exposed an implementation detail of the snapshot cache that did not survive the C ABI review and had no use case that was not better served by `notice_sync plus an explicit noticeboard()` read.