Instruction file imported from dxos/dxos (.cursor/rules/dxos.mdc). Copyright stays with the author.

DXOS Rules

Key preferences:

• Write in TypeScript by default.
• Prefer functional programming patterns.
• Follow React best practices and hooks patterns.
• Use TailwindCSS for React styles.
• Unit test examples when relevant.

When writing code:

• Include type definitions.
• Add JSDoc comments for public functions.
• Keep components pure and composable.
• Use proper error handling with Effect; never put untyped Error in an Effect's error type parameter — use BaseError.extend or Data.TaggedClass.
• Include proper event handler types for React components.
• All comments should be in English and end with a period.

Technologies to consider:

• Use Effect-TS for schema validation.
• Automerge for state management.
• Codemirror v6 for editor integrations.

Monorepo tools:

• moon for monorepo management.
• pnpm for package management.
• vitest
• vite

Testing:

• Place test files near the module they test with "module_name.test.ts" format.
• Use vitest with describe and test apis (don't use it). it.effect is an exception to this rule.
• Don't write tests at top-level, instead make sure they are wrapped in a describe block.
• Prefer importing expect from test context: test('foo', ({ expect }) => ...)
• File layout: suite config first (beforeEach / afterEach, shared fixtures), then tests. Put helper functions at the bottom of the test file, after the closing describe — never between imports and the suite.
• Test body layout: setup at the top of each test (peer, db, queues, testLayer, etc.), then the scenario and assertions.