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Bun runtime CLAUDE.md

CLAUDE.md for TypeScript projects on Bun 1.2+: bun test, Bun.serve, built-in SQLite/Postgres, and bundling.

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Save this as CLAUDE.md in your repository root, commit it, and your agent will pick it up automatically. Edit the commands to match your project.

# CLAUDE.md: Bun project

## Commands
- Install: `bun install` (lockfile `bun.lock`) · Run: `bun run dev` · Test: `bun test` · Types: `bunx tsc --noEmit`

## Use Bun's built-ins first
- HTTP: `Bun.serve({ routes: {...}, fetch })` instead of adding Express.
- Files: `Bun.file(path)` / `Bun.write`. Shell scripts: `import { $ } from "bun"`.
- SQLite via `bun:sqlite`; Postgres via `Bun.sql` if the project uses it. Use parameterized queries (tagged templates), never string concatenation.
- Env vars load from `.env` automatically; read with `Bun.env` or `process.env`. Don't add `dotenv`.
- Password hashing: `Bun.password.hash/verify`.
- Tests: `import { test, expect, mock } from "bun:test"`. Don't add Jest or Vitest.

## Rules
- Keep code Node-compatible only if `package.json` says the package must run on Node too.
- Use `bun add` / `bun add -d` so the lockfile stays in sync; never edit `bun.lock` by hand.
- TypeScript runs directly; no build step for scripts. Use `bun build` only for shipping bundles.

## Don't
- Don't use `npm`/`yarn`/`pnpm` commands in this repo.

## Done when
`bun test` and `bunx tsc --noEmit` pass.