diff --git a/modules/encode/default.nix b/modules/encode/default.nix
index 101b9d7..62b2bd1 100644
--- a/modules/encode/default.nix
+++ b/modules/encode/default.nix
@@ -9,6 +9,7 @@
     hdr10plus_tool
     jq
     mediainfo
+    mkvtoolnix-cli
   ];