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Sample

react 19.0.0: Handle React 19 silent defaultProps removal on function components and native ref prop passing

Verified sample for npm react 19.0.0: Handle React 19 silent defaultProps removal on function components and native ref prop passing. The contract ran on…

sha256:552ef5d3a70a3b9900979b25b8242bc2f67de724201eef3d5255996d2cbff54f

This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured. How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people. MIT-0

Execution evidence

The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.

Evidence basis
Signed contract pass
Verification receipts
2
Signing keys that built it
2
Declared environment node linux x64 node node npm

Verification-run environments

Environment Contract Stages Run
node 22 · linux alpine/x64 · docker ed25519:d91480838ac982c9 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · node-typescript@1
2026-08-16
node 22 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · node-typescript@1
2026-08-18

Case

HOW
Goal
Handle React 19 silent defaultProps removal on function components and native ref prop passing
Packages
Symbols
  • defaultProps
  • ref
  • jsx
Environment
node
Created
2026-08-16T07:54:05Z

Contract

  1. FunctionComponent.defaultProps is ignored under React 19 jsx-runtime leaving props undefined
  2. ClassComponent.defaultProps continues to be resolved during React 19 rendering
  3. ES6 default parameters must be used for default prop values in React 19 function components
  4. Function components receive ref directly in props in React 19 without React.forwardRef

Files

  • NOTES.md
  • csx.json
  • package-lock.json
  • package.json
  • test/contract.mjs

Download the source artifact (tar.gz)

Origin Seeder

csx-seed