diff --git a/test/diagnostics/dune b/test/diagnostics/dune
index a804658..654a395 100644
--- a/test/diagnostics/dune
+++ b/test/diagnostics/dune
@@ -14,5 +14,6 @@
 
 (rule
  (alias runtest)
+ (package opam-0install)
  (action
   (diff test_diagnostics.expected test_diagnostics.output)))