shadlet 0.4.0

shadlet 0.4.0 is a major runtime and release-readiness update. it expands the Python-first APIs, improves server-driven tables and accessibility, and adds extension tooling, deployment examples, and broader verification.

added

• ui.DataTable now supports controlled row selection, loading and error states, retry callbacks, per-column filters, column visibility, responsive scrolling, accessible sort announcements, and cancellation of superseded asynchronous server queries.
• shadlet extension create scaffolds a separately packaged Python and React extension. shadlet extension check validates its manifest and bundled assets.
• deployment examples include a multi-stage, non-root Docker image, a Render Blueprint, and a health check endpoint at GET /healthz.
• opt-in runtime benchmarks cover 10k-row table workloads, 1k-node rendering and protocol serialization, and concurrent updates across 50 sessions.
• representative axe-core accessibility checks and Chromium Playwright flows cover forms, feedback, tables, packaged extensions, URL state, and server-side table search.
• app.run() recognizes the platform PORT environment variable, with documented precedence and validation.

changed

• React protocol validation now uses Zod 4; the renderer development server is updated to Vite 7.3.7.
• extension discovery now registers transactionally and remains idempotent after success.
• pydantic form validation preserves multiple messages associated with the same field.
• built-in project templates now target Shadlet 0.4.0.

fixed

• server-side table search reliably dispatches changed queries to Python.
• closed sessions reject newly started background tasks without leaving them marked as running.
• form labels and controls now have improved accessible-name and id associations, including slider inputs and date-picker triggers.

verification

• Python: Ruff lint and formatting, mypy, and Pyright passed; all 145 pytest tests passed.
• renderer: ESLint, Prettier, and TypeScript checks passed; all 27 Vitest tests and all 3 Playwright tests passed; the production build succeeded.
• documentation: strict MkDocs build passed.
• packaging: wheel and source distribution built; renderer assets and built-in templates were verified in the wheel; an isolated wheel installation smoke test passed.
• dependencies: production npm audit --omit=dev reported zero vulnerabilities.
• GitHub CI, including the Docker deployment-example build, passed for the release commit. the tag-triggered release workflow successfully published both distributions to this GitHub release and PyPI.

see the changelog, documentation, and PyPI package.