stack2nix

About

stack2nix automates conversion from Stack configuration file to Nix expressions. The purpose is to map stack.yaml one-to-one into Nix expressions.

stack2nix high-level workflow:

• Generate stackage snapshot to determine complete fixed version list of packages based on resolver
• apply any additional configuration (local packages, extra dependencies, etc) from stack.yaml
• generate complete list of dependencies to Nix expressions, replacing upstream hackage-packages.nix

Installation

There are three options. The first - using Nix is recommended. If there are difficulties please file an issue.

Nix (recommended)

1. Install Nix.
2. Clone this repo.
3. Run nix-build to build.

Stack

1. Install Nix.
2. Clone this repo.
3. Run stack install --nix to install.

Virtual Machine

1. Install VirtualBox and Vagrant.
2. Clone this repo.
3. Run ./scripts/vagrant.sh and take a coffee break.
4. If there are no errors, log into the VM: vagrant ssh.

Usage

Nix expressions generated by stack2nix require NixOS 17.09 or later.

Local Packages

Sometimes it's convenient to build local Haskell packages. Assuming the current directory is a locally maintained fork of Pandoc:

    $ stack2nix . > default.nix
    $ nix-build -A pandoc

Remote Packages

Stack2nix can generate a nix expressions for Haskell packages hosted in git repositories.

    $ stack2nix --revision 242e2a064f6a32b22e1599bbfe72e64d7b6203b8 https://github.com/jgm/pandoc.git > demo.nix
    $ nix-build -A pandoc demo.nix

Testing

Run ./scripts/travis.sh to build and test.