Nixpacks

Spec sheet

Purpose

Nixpacks analyzes an application source directory and produces an OCI-compliant image that can be deployed anywhere.Read 9 Oct 2026 · nixpacks.com

Integrations

Nixpacks is available as a builder on Railway and Coolify.Read 9 Oct 2026 · nixpacks.com

Architecture limit

Nixpacks does not support building multiple architectures in one build; separate builds are required before creating a multi-architecture image.Read 4 Oct 2026 · nixpacks.com

Automatic detection

Language providers are matched against the app source directory and suggest Nix packages and install, build, and start commands.Read 4 Oct 2026 · nixpacks.com

Build limitation

Nixpacks does not support producing multiple architectures in a single build.Read 9 Oct 2026 · nixpacks.com

Build process

It generates a reproducible build plan from detected language providers and uses Docker BuildKit to create an OCI image.Read 9 Oct 2026 · nixpacks.com

Caching

Providers cache directories during install and build phases by default, and users can change the cache key or disable caching.Read 4 Oct 2026 · nixpacks.com

Configuration

Builds can be customized with Nixpacks TOML or JSON configuration files, environment variables, or CLI flags.Read 9 Oct 2026 · nixpacks.com

Customization

Users can override provider suggestions, add Nix or Apt packages, and customize build and start commands.Read 4 Oct 2026 · nixpacks.com

Distribution

Install options include Homebrew and MacPorts for macOS, Scoop and MSI packages for Windows, Debian packages, shell scripts, and building from source.Read 9 Oct 2026 · nixpacks.com

GitHub Actions

The documentation includes a GitHub Actions deployment guide for Nixpacks.Read 9 Oct 2026 · nixpacks.com

Installation platforms

Installation options include macOS through Homebrew or MacPorts, Windows through Scoop or MSI releases, and Debian or Ubuntu through .deb releases.Read 4 Oct 2026 · nixpacks.com

Language support

The documentation lists providers for languages including Python, Node, Go, Java, Ruby, Rust, and Swift.Read 9 Oct 2026 · nixpacks.com

Maintenance status

Nixpacks is in maintenance mode and is not under active development; its documentation recommends Railpack as a replacement.Read 9 Oct 2026 · nixpacks.com

Open source

The project describes itself as open source on GitHub and says it was started by Railway.Read 9 Oct 2026 · nixpacks.com

Packages and commands

Users can add Nix or Apt packages and override build and start commands.Read 9 Oct 2026 · nixpacks.com

Python support

The Python provider detects files such as main.py, requirements.txt, pyproject.toml, and Pipfile, and supports multiple package managers including pip, Poetry, PDM, and uv.Read 9 Oct 2026 · nixpacks.com

Reproducible plans

A build plan can be saved and reused later to build the image with the same configuration.Read 4 Oct 2026 · nixpacks.com

Runtime requirement

Building and running the output image uses Docker, and the documentation describes image creation with docker build.Read 4 Oct 2026 · nixpacks.com

Where Specifiction places it

• Container Build Tools#28 of 347.1