Add nix support

default.nix

@@ -0,0 +1,31 @@
+{ mkDerivation, aeson, ansi-terminal, async, base, directory
+, filepath, formatting, gitrev, hspec, hspec-discover, mtl
+, optparse-applicative, path, path-io, process, QuickCheck
+, silently, stdenv, stm, temporary, time, transformers
+, typed-process, yaml, git, zlib, zsh
+}:
+mkDerivation {
+  pname = "hapistrano";
+  version = "0.3.10.0";
+  src = ./.;
+  isLibrary = true;
+  isExecutable = true;
+  enableSeparateDataOutput = true;
+  libraryHaskellDepends = [
+    aeson ansi-terminal base filepath formatting gitrev mtl path
+    process stm time transformers typed-process
+  ];
+  executableHaskellDepends = [
+    aeson async base formatting gitrev optparse-applicative path
+    path-io stm yaml
+  ];
+  testHaskellDepends = [
+    base directory filepath hspec mtl path path-io process QuickCheck
+    silently temporary
+  ];
+  testSystemDepends = [ git zlib zsh ];
+  testToolDepends = [ hspec-discover ];
+  homepage = "https://github.com/stackbuilders/hapistrano";
+  description = "A deployment library for Haskell applications";
+  license = stdenv.lib.licenses.mit;
+}

release.nix

@@ -0,0 +1,8 @@
+let
+  pkgs = import <nixpkgs> { };
+in
+pkgs.haskellPackages.callPackage ./default.nix { 
+ git = pkgs.git;
+ zlib = pkgs.zlib;
+ zsh = pkgs.zsh;
+}

result

@@ -0,0 +1 @@
+/nix/store/si2zr3yr3vcigvvviakiiil3562lm32h-hapistrano-0.3.10.0