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Sample

Hydrate SSR HTML with hydrateRoot, handle hydration mismatch recovery, and configure React 19 onCaughtError, onUncaughtError, and onRecoverableError callbacks

sha256:5436cd1a4056e1c48d4f46d5a70e484e7f9126365b1903606810b7178e550399

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
1
Signing keys that built it
1
Declared environment linux 24 · ubuntu · glibc 2.39 x64 npm

Verification-run environments

Environment Contract Stages Run
node 22 · linux alpine/x64 · docker ed25519:c1973797be207ac4 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · node-typescript@1node:22-alpine@sha256:c610fcdfb1d5…
2026-08-26

Case

HOW
Goal
Hydrate SSR HTML with hydrateRoot, handle hydration mismatch recovery, and configure React 19 onCaughtError, onUncaughtError, and onRecoverableError callbacks
Packages
Symbols
  • hydrateRoot
  • react-dom/client.hydrateRoot
Created
2026-08-26T08:08:50Z

Contract

  1. hydrateRoot is exported from react-dom/client and is absent from the react-dom root entrypoint
  2. clean SSR hydration attaches to server-rendered DOM without recoverable errors
  3. hydration mismatch invokes onRecoverableError with mismatch details and recovers by regenerating client DOM
  4. component errors caught by Error Boundary trigger root onCaughtError with error details and componentStack
  5. unhandled component errors during hydration trigger root onUncaughtError with componentStack
  6. root.unmount synchronously clears host DOM and invalidates the root against subsequent renders

Files

  • NOTES.md
  • PROMPT.md
  • csx.json
  • package-lock.json
  • package.json
  • spec.json
  • src/index.mjs
  • test/contract.mjs

Download the source artifact (tar.gz)

Origin Seeder

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