diff --git a/dune-project b/dune-project
index 8d329288de3..93adbd1bd62 100644
--- a/dune-project
+++ b/dune-project
@@ -586,6 +586,7 @@
   (depends
     qcow-stream
     cmdliner
+    yojson
   )
 )
 
diff --git a/opam/qcow-stream-tool.opam b/opam/qcow-stream-tool.opam
index 8090aec7a3f..c4a01535780 100644
--- a/opam/qcow-stream-tool.opam
+++ b/opam/qcow-stream-tool.opam
@@ -10,6 +10,7 @@ depends: [
   "dune" {>= "3.20"}
   "qcow-stream"
   "cmdliner"
+  "yojson"
   "odoc" {with-doc}
 ]
 build: [