[jfrolich]

The JSX PPX moved every attribute of a component's function onto the generated props => make(props) wrapper. For an async component that wrapper is a sync function returning make's promise, so

@react.component
let make = @directive("'use cache'") async (~id) => ...

compiled to function Name(props) { 'use cache'; return make(props); }, which Next.js rejects ("'use cache' functions must be async"). A directive on an async component now stays on make, which the wrapper then reduces to. Sync components are unchanged: their wrapper inlines make, so the directive already lands on the one function.

[github-actions]

Changelog

🐛 Bug fix

• JSX v4: keep @directive on an async component's own function instead of its generated sync wrapper, so @react.component let make = @directive("'use cache'") async (...) => ... compiles to an async function starting with 'use cache', which Next.js accepts.

Semantic Diff

1 commit · Full page

✏️ JSX v4: keep an async component's @directive on its own function

_{19ea2c4 · open-session-os-tella-dev[bot] + Jaap Frolich · Nov 09, 2026, 19:12 UTC · edited}

The JSX PPX moved every attribute of a component's function onto the generated props => make(props) wrapper. For an async component that wrapper is a sync function returning make's promise, so

@react.component let make = @directive("'use cache'") async (~id) => ...

compiled to function Name(props) { 'use cache'; return make(props); }, which Next.js rejects ("'use cache' functions must be async"). A directive on an async component now stays on make, which the wrapper then reduces to. Sync components are unchanged: their wrapper inlines make, so the directive already lands on the one function.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 81.92%. Comparing base (b82d944) to head (8f971d7).
⚠️ Report is 5 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #9289   +/-   ##
=======================================
  Coverage   81.92%   81.92%           
=======================================
  Files         456      456           
  Lines       65464    65468    +4     
=======================================
+ Hits        53631    53635    +4     
  Misses      11833    11833           

Files with missing lines	Coverage Δ
compiler/syntax/src/jsx_v4.ml	86.98% <100.00%> (+0.09%)	⬆️

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commit: 8f971d7

[cknitt]

@jfrolich could you rebase on latest master, and have your agent follow the new changelog workflow?