bun-dev_skill

Overview

This skill provides concise guidance and patterns for developing with the Bun runtime, including Bun.serve, bun:sqlite, bun:test, and Bun native APIs. It focuses on idiomatic, zero-dependency workflows: file I/O, SQLite usage, HTTP and WebSocket servers, testing, password hashing, shell integration, and building. Use it to replace Node-centric patterns with Bun-native alternatives and to follow safe, high-performance defaults.

How this skill works

The skill inspects mentions of Bun, bun:test, Bun.serve, bun:sqlite, and other Bun-specific patterns and returns targeted advice, code snippets, and best practices. It highlights native APIs like Bun.file, Bun.write, Bun.password, Bun.serve, and bun:sqlite, and maps common tasks—database queries, transactions, file streaming, testing, and builds—to Bun idioms. It also enforces safety rules: prepared statements, environment validation, and proper resource cleanup.

When to use it

• Building HTTP or WebSocket servers with Bun.serve or Hono on Bun
• Working with SQLite using bun:sqlite for local databases and transactions
• Writing scripts that read/write files or stream large payloads with Bun.file and Bun.write
• Running tests and coverage with bun:test and test lifecycle hooks
• Hashing and verifying passwords using Bun.password for secure auth flows
• Executing shell commands and CI tasks via the $ template and Bun.spawn

Best practices

• Prefer Bun native APIs (Bun.file, Bun.write, Bun.env) over Node fs/process shims
• Always use prepared statements and named parameters for SQL to avoid injection
• Use transactions for multi-step DB operations and close Database instances when done
• Hash passwords with argon2id and verify via Bun.password; never store plaintext
• Validate environment variables at startup with a schema (zod recommended)
• Use bun:test watch/coverage for fast feedback and isolate DB state in beforeEach/afterEach

Example use cases

• Create a small API with Bun.serve and route handling via Hono, serving JSON and static assets
• Implement user registration: hash passwords, insert into bun:sqlite using prepared statements, return safe responses
• Build a CLI or background job that reads large files with Bun.file.stream and writes processed output with Bun.write
• Write fast unit and integration tests with bun:test using in-memory SQLite and lifecycle hooks
• Bundle a production binary with bun build --compile for distribution across platforms