[mbianchidev]

Summary

• Pin Node.js 26.12.1, the latest stable release verified on 2026-10-25, in .nvmrc.
• Make the Pages validation/build workflow read that same pin instead of selecting Node.js 22.
• Update local setup guidance, including nvm install && nvm use, without raising the existing toolchain compatibility minimum.
• Leave React and React DOM at 19.3.1, already the latest stable versions. This repository does not use Next.js, Go, Java, or Python as application/build runtimes; educational roadmap content is unchanged.
• Keep dependency manifests and the lockfile unchanged.

Verification

Using a checksum-verified official Node.js 26.12.1 binary and its bundled npm 11.20.0:

• npm ci: succeeded, 0 vulnerabilities.
• npm test: 20 passed.
• npm run lint: passed.
• npm run build: passed.
• npm run test:e2e: 44 desktop/mobile tests passed, including the production build served by Playwright.
• Parsed the workflow YAML and verified that CI reads .nvmrc and local validation used its exact version.

The local macOS installation emitted an optional fsevents@2.3.3 install-script approval warning. A subsequent npm install-scripts ls reported no packages with unreviewed install scripts; no approval/configuration changes were needed and all checks passed.

Release sources: Node.js release index, React release tags, React DOM release tags.

Draft for human review. No merge requested.

[Copilot]

🟡 Changes recommended

The availability of the pinned Node.js 26.12.1 release needs to be reconciled before approval.

No open issues 🎉

What changed in this PR

This pull request standardizes local development and GitHub Pages validation on Node.js 26.12.1 while preserving the existing compatibility minimum and leaving application dependencies unchanged.

Changes:

• Pins Node.js 26.12.1 in .nvmrc.
• Updates Pages CI to read the version from .nvmrc.
• Updates README and contributor setup guidance with the pinned runtime and nvm workflow.

File	Description
README.md	Documents Node.js 26.12.1 while retaining the existing compatibility minimum.
CONTRIBUTING.md	Updates local setup guidance and adds the nvm install && nvm use workflow.
.nvmrc	Pins the repository to Node.js 26.12.1.
.github/​workflows/​deploy.yml	Configures GitHub Actions to use the version specified by .nvmrc.

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