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Welcome to Bun Installation Quickstart TypeScript TypeScript 6 and 7

Watch Mode Debugging REPL bunfig.toml File Types Module Resolution JSX Auto-install Plugins File System Router

Cookies File I/O Streams Binary Data Archive SQL SQLite S3 Redis Workers Environment Variables Shell Spawn WebView Cron Node-API FFI C Compiler Transpiler CSRF Protection Secrets Console TOML YAML Markdown JSON5 JSONL HTMLRewriter Image Hashing Glob Semver Color Utils Globals Bun APIs Web APIs Node.js Compatibility

Append content to a file Write a string to a file Write a Blob to a file Write a file to stdout Copy a file to another location Write a file incrementally Write a Response to a file Write to stdout Write a ReadableStream to a file Delete a file

File SystemWrite file

Append content to a file

Bun implements the node:fs module, which includes the fs.appendFile and fs.appendFileSync functions for appending content to files.

Watch a directory for changes

Bun implements the node:fs module, including the fs.watch function for listening for file system changes.

Write a string to a file

Use Bun.write() to write a string to disk at an absolute path . The first argument is a destination ; the second is the data to write.