diff --git a/ci/build-deps.nix b/ci/build-deps.nix
index daa90e4c70e992a10b3a5d097446e88ee1280075..b394210145568d2eed31683b8b2ec45d28e16896 100644
--- a/ci/build-deps.nix
+++ b/ci/build-deps.nix
@@ -10,4 +10,5 @@ with pkgs;
   bzlib = [ bzip2 ];
   hmatrix = [ blas liblapack ];
   hexpat = [ expat ];
+  hgmp = [ gmp ];
 }
diff --git a/ci/config.sh b/ci/config.sh
index 523b2c70fd5a4a12986c5c997fa7e5dcf7da29a0..96e198e521e117e6fc1bbd872f9d0bfc50ba6ff4 100644
--- a/ci/config.sh
+++ b/ci/config.sh
@@ -99,6 +99,7 @@ extra_package generic-lens
 extra_package microstache
 extra_package singletons
 extra_package servant
+extra_package hgmp
 
 # Build-tool packages
 build_tool_package alex