diff --git a/nix/internal-tests.nix b/nix/internal-tests.nix
index 1e144928c107a3fbffa355008c6e4057d5f29a29..9e71c73b64f5b54d15d985b1f2337a2860fd97da 100644
--- a/nix/internal-tests.nix
+++ b/nix/internal-tests.nix
@@ -30,11 +30,13 @@
 , ocamlgraph
 , ocp-indent
 , ppx_deriving
+, ppx_deriving_yaml
 , ppx_deriving_yojson
 , ppx_import
 , yojson
 , which
 , why3
+, yaml
 , zarith
 , zmq
 # Frama-C tests
@@ -87,10 +89,12 @@ stdenvNoCC.mkDerivation rec {
     ocamlgraph
     ocp-indent
     ppx_deriving
+    ppx_deriving_yaml
     ppx_deriving_yojson
     ppx_import
     yojson
     which
+    yaml
     why3
     zarith
     zmq