stack-nix.txt

chris@renzo ~> cat ~/.stack/config.yaml 
# This file contains default non-project-specific settings for 'stack', used
# in all projects.  For more information about stack's configuration, see
# http://docs.haskellstack.org/en/stable/yaml_configuration.html
#
nix:
  enable: true
  pure: false
  shell-file: /home/chris/.stack/shell.nix

chris@renzo ~> cat ~/.stack/shell.nix 
{ pkgs ? import <nixpkgs> {}, ghc ? pkgs.ghc }:

with pkgs;

haskell.lib.buildStackProject {
  name = "default-stack-shell";
  inherit ghc;
  buildInputs = [ zlib ];

  # https://github.com/commercialhaskell/stack/issues/2358
  LANG = "en_US.UTF-8";

  # https://github.com/commercialhaskell/stack/commit/568938da
  TMPDIR = "/tmp";
}