bun-run

Execute files and package scripts

TLDR

Run a JavaScript/TypeScript file

$ bun run [script.ts]

Run a package.json script

$ bun run [start]

Run file in watch mode

$ bun --watch run [script.ts]

List available scripts

$ bun run

Evaluate code string

$ bun run --eval "[console.log('hello')]"

Evaluate and print result

$ bun run --print "[1 + 2]"

Run with environment file

$ bun run --env-file [.env] [script.ts]

SYNOPSIS

bun run [options] file|script [arguments]bun file|script [arguments]

bun run executes JavaScript, TypeScript, and JSX files using Bun's fast native transpiler. It can also run package.json scripts with lifecycle hook support.The command can be shortened to just bun followed by the file or script name, though built-in commands take precedence.

PARAMETERS

--watch

Re-run on file changes. Must be placed before `run` in the command.

--hot

Enable hot reloading instead of full restart on file changes.

--eval, -e code

Evaluate argument as script

--print, -p code

Evaluate and print result

--env-file file

Load environment variables from file

--cwd directory

Set working directory

--silent

Suppress script output

--smol

Reduce memory usage at the cost of performance by running the garbage collector more frequently.

--if-present

Exit without error if the entrypoint or script does not exist.

--filter pattern

Run scripts in matching workspace packages by name pattern.

--bun

Force the script to run through Bun's runtime, overriding shebang lines.

BEHAVIOR

Source files

Paths starting with ./ or absolute paths run as source files

Package scripts

Scripts defined in package.json are executed with lifecycle hooks (pre/post)

Resolution

With bun run, package.json scripts take precedence over files with same name

LIFECYCLE HOOKS

Bun respects pre and post lifecycle hooks. Running bun run build will execute prebuild, build, and postbuild in order. If a pre-script fails, the main script is not executed.

INSTALL

sudo pacman -S bun

brew install bun

nix profile install nixpkgs#bun

CAVEATS

TypeScript and JSX are transpiled on-the-fly without configuration. Startup time is significantly faster than npm run. Some Node.js-specific APIs may not be available.