Run your project's tasks. 66x faster.

A zero-overhead task runner written in Rust. One command for every project. nr <task> detects whatever your project uses (npm scripts, a Makefile, a justfile, Cargo, pyproject, uv, a Pipfile, a Procfile or a Taskfile) and runs the task with no Node.js startup and no overhead.

Median of 10 runs measured with hyperfine (--shell=none) running echo test on macOS 26.5.1 (Apple Silicon). Your mileage may vary.

The table above is nr versus other npm script runners. nr also replaces the Python launchers natively: poetry, pipenv and pdm each boot a Python interpreter on every run, so nr finds the project virtualenv and execs your task directly instead.

What about uv? It's already native and fast, so nr just delegates to uv run (detecting uv projects via uv.lock) for one command across every project, not for speed.

curl -fsSL https://raw.githubusercontent.com/dawsbot/nr/main/install.sh | sh

Works on macOS, Linux, and Windows (via Git Bash/WSL).

# List every task nr can find in this project
nr

# Run a task by name
nr build

# Pass arguments through to the task
nr test -- --watch

nr walks up from your current directory to the nearest folder containing a recognized manifest, then merges every task it finds. If several manifests live side by side, all of their tasks are listed and package.json wins any name collision.

For delegated tools (make, just, cargo, task, uv), nr replaces itself with a single exec call, so it adds no measurable overhead on top of the tool you were going to run anyway. That tool does need to be installed and on your PATH.

For the Python launchers (poetry, pdm, pipenv), nr skips the launcher entirely: it resolves the project virtualenv (an active $VIRTUAL_ENV, an in-project .venv, or pdm's __pypackages__), puts its bin/ on PATH, and execs the task directly, avoiding the Python interpreter startup those tools pay on every run. When no local virtualenv can be found it falls back to poetry run / pdm run / pipenv run, so the result is always correct.

Make your AI coding assistant use nr instead of npm run by adding this instruction to its config:

Use `nr` instead of `npm run` for running package.json scripts. It's a faster drop-in replacement.

Add to ~/.claude/CLAUDE.md (global) or CLAUDE.md in your project root:

Use `nr` instead of `npm run` for running package.json scripts.

Add to .cursorrules in your project root:

Use `nr` instead of `npm run` for running package.json scripts.

Add to .github/copilot-instructions.md in your repo:

Use `nr` instead of `npm run` for running package.json scripts.

Add to .windsurfrules in your project root:

Use `nr` instead of `npm run` for running package.json scripts.

Add to .zed/settings.json in your project:

{
  "assistant": {
    "instructions": "Use `nr` instead of `npm run` for running package.json scripts."
  }
}

No Node.js startup. npm, yarn, and pnpm all bootstrap Node.js before doing anything. That's 50-100ms before your script even starts. nr is a native binary—it starts instantly.

Direct exec. On Unix systems, nr uses the exec() syscall to replace itself with your command. No fork, no wait, no overhead. Your script runs in the same process slot.

No shell when none is needed. If a script has no shell metacharacters (most don't: vitest, tsc -p ., eslint src), nr skips /bin/sh entirely and execs the program directly. That saves several milliseconds of shell startup, and your extra arguments arrive as real argv entries instead of being re-split by the shell.

Minimal parsing. We only read the scripts field from package.json. Not dependencies, not lockfiles, not node_modules. Just scripts.

Tiny binary. 377KB. No runtime, no GC, no framework. Just machine code.

nr is intentionally minimal:

• No pre/post lifecycle scripts (use nr pretest && nr test if needed)
• No workspaces support

If you need these features, use npm. If you want speed, use nr.

git clone https://github.com/dawsbot/nr
cd nr
cargo build --release
cp target/release/nr /usr/local/bin/

Experimental. Works on my machine. Report issues at GitHub.

MIT