1 files changed, 4 insertions, 2 deletions

diff --git a/trivmix.nix b/trivmix.nix
index bd9c278..8ddce63 100644
--- a/trivmix.nix
+++ b/trivmix.nix
@@ -1,6 +1,6 @@
 { mkDerivation, base, case-insensitive, data-default, directory
-, explicit-exception, filelock, filepath, heredoc, hinotify, jack
-, optparse-applicative, process, refined, scientific, stdenv
+, explicit-exception, filelock, filepath, heredoc, hinotify, hpack
+, jack, optparse-applicative, process, refined, scientific, stdenv
 , systemd, th-lift, transformers, unix
 }:
 mkDerivation {
@@ -12,10 +12,12 @@ mkDerivation {
   libraryHaskellDepends = [
     base case-insensitive data-default refined scientific th-lift
   ];
+  libraryToolDepends = [ hpack ];
   executableHaskellDepends = [
     base directory explicit-exception filelock filepath heredoc
     hinotify jack optparse-applicative process refined scientific
     systemd transformers unix
   ];
+  preConfigure = "hpack";
   license = stdenv.lib.licenses.publicDomain;
 }