Can Rspack Cancel Ongoing Compilation on New File Changes (Watch Mode)?

[kelp-vishal]

Hi team,

We’re using Rspack in dev/watch mode for a large Angular + Nx + Module Federation project.

Rebuild time is ~30 seconds. If a rebuild (A) is in progress and we modify another file (B), Rspack finishes A first and then starts a new rebuild for B. So if we edit B halfway through A, total wait becomes ~45 seconds.

Is there any option in Rspack to:

Cancel an ongoing compilation when new file changes are detected, and

Immediately restart compilation using the latest state (A + B changes)?

Or is queued rebuild the intended and only behavior in watch mode?

We’re trying to improve dev-loop efficiency for large projects.

Thanks.

[hardfist]

Rspack doesn't support cancel ongoing compilation and it's no easy to support it

[MukundaKatta]

Yep, that's the current behavior — Rspack queues file changes during a compilation and processes them after. Cancel-on-change is blocked by a few SWC-level invariants and is non-trivial to thread through the pipeline. Partial mitigation: bump watchOptions.aggregateTimeout to ~300ms so multiple saves coalesce into one rebuild. For huge MFE monorepos, splitting the federation hosts into separate dev servers (so B's edit only rebuilds B's host) is usually the bigger speed-up anyway.