Stream: git-wasmtime

Topic: wasmtime / PR #13620 feat: allow custom fiber APIs

view this post on Zulip Wasmtime GitHub notifications bot (Jun 12 2026 at 09:47):

rvolosatovs opened PR #13620 from rvolosatovs:feat/custom-fiber to bytecodealliance:main:

Add support for custom embedder-supplied fiber implementations, similar to e.g. custom-virtual-memory feature and others that already exist.

I'm not sure whether custom-fiber or custom-stack-switch is more appropriate, went for the one matching the crate name.

For my concrete use case, this is sufficient to allow running Wasmtime with cranelift in interpreter mode using Pulley with async/component-model-async features enabled, compiled to wasm32-unknown-unknown with a bit of JS glue based on JSPI.

view this post on Zulip Wasmtime GitHub notifications bot (Jun 12 2026 at 09:47):

rvolosatovs requested pchickey for a review on PR #13620.

view this post on Zulip Wasmtime GitHub notifications bot (Jun 12 2026 at 09:47):

rvolosatovs requested wasmtime-core-reviewers for a review on PR #13620.

view this post on Zulip Wasmtime GitHub notifications bot (Jun 12 2026 at 09:51):

rvolosatovs converted PR #13620 feat: allow custom fiber APIs to a draft.

view this post on Zulip Wasmtime GitHub notifications bot (Jun 12 2026 at 09:53):

rvolosatovs edited PR #13620:

Add support for custom embedder-supplied fiber implementations, similar to e.g. custom-virtual-memory feature and others that already exist.

I'm not sure whether custom-fiber or custom-stack-switch is more appropriate, went for the one matching the crate name.

For my concrete use case, this is sufficient to allow running Wasmtime with cranelift in interpreter mode using Pulley with async/component-model-async features enabled, compiled to wasm32-unknown-unknown with a bit of JS glue based on JSPI in the browser or node.js

view this post on Zulip Wasmtime GitHub notifications bot (Jun 12 2026 at 09:58):

rvolosatovs updated PR #13620.

view this post on Zulip Wasmtime GitHub notifications bot (Jun 12 2026 at 10:00):

rvolosatovs updated PR #13620.

view this post on Zulip Wasmtime GitHub notifications bot (Jun 12 2026 at 10:00):

rvolosatovs updated PR #13620.

view this post on Zulip Wasmtime GitHub notifications bot (Jun 12 2026 at 10:02):

rvolosatovs updated PR #13620.

view this post on Zulip Wasmtime GitHub notifications bot (Jun 12 2026 at 10:04):

rvolosatovs has marked PR #13620 as ready for review.

Last updated: Jul 29 2026 at 05:03 UTC