feat: hot-swap route handlers in dev mode#41
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Route handlers were captured by value in closures at startup and never
refreshed — changing an API handler required a full server restart.
Add a `routeModule` option pointing to the routes file. In dev mode,
when a dependency of that module changes the dev watcher re-bundles it
via `Bun.build({ packages: 'external' })`, reimports with cache
busting, and updates mutable handler maps that route closures read
lazily on each request. WS handlers already used lazy lookup via
`wsHandlersMap` so only API, SSE, and page serverProps/actions needed
new indirection.
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Mochi review reportTry this PRExpand instructionsgh run download -R khromov/mochi 26543966964 -n mochi-framework-pr -D /tmp/mochi-pr && bun i /tmp/mochi-pr/mochi-framework-pr.tgzDependency reportExpand reportLines of codepackages/mochi
Unchanged: packages/docs
packages/site
Unchanged: packages/demos
Unchanged: packages/minimal
Unchanged: packages/cli
Unchanged: |
Probe for ./src/routes.ts (then .js) in dev mode so route HMR works out of the box without explicit config. routeModule option remains as an override. Remove the now-redundant explicit routeModule from all three site configs.
Replace non-null assertions on HMR handler map lookups with fallbacks to the originally captured handler, and sequence the initial route module build through the reload chain to prevent a race with early file changes.
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May 29, 2026
🤖 I have created a release *beep* *boop* --- <details><summary>mochi-framework: 0.5.0</summary> ## [0.5.0](mochi-framework-v0.4.0...mochi-framework-v0.5.0) (2026-05-28) ### Features * hot-swap route handlers in dev mode ([#41](#41)) ([106a4a2](106a4a2)) * opt-in route warmup to pre-warm static pages at startup ([#64](#64)) ([9f28ede](9f28ede)) * replace highlight.js with Shiki ([#54](#54)) ([3d2dc6a](3d2dc6a)) ### Code Refactoring * replace `cookie` npm package with Bun native cookie APIs ([#60](#60)) ([4e0d953](4e0d953)) * run all tests in per-file isolation, drop .isolated.test.ts suffix ([#55](#55)) ([68cdc06](68cdc06)) * vendor debounce, drop npm dependency ([#63](#63)) ([d465fea](d465fea)) * vendor json-format-highlight, drop npm dependency ([#61](#61)) ([0b88399](0b88399)) </details> --- This PR was generated with [Release Please](https://github.com/googleapis/release-please). See [documentation](https://github.com/googleapis/release-please#release-please). Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
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Summary
serverProps/actionswere captured by value at startup and never refreshed — changing a handler required a full server restartrouteModuleoption toMochiServeOptionspointing to the routes fileBun.build({ packages: 'external' }), reimports with cache busting, and hot-swaps handler references through mutable mapswsHandlersMap— only API, SSE, and page routes needed new indirectiondevelopment && routeModuleTest plan
bun run checkspasses (lint, format, typecheck, tests)/health, edited handler to addhmr: truefield, hit again — response reflected the change without restartserverPropsHMR by editing a data-loading function