diff --git a/dune-project b/dune-project
index ceae9ab2..617f0806 100644
--- a/dune-project
+++ b/dune-project
@@ -44,6 +44,8 @@
   (depends
     (moonpool (= :version))
     (ocaml (>= 5.0))
+    (qcheck-core (and :with-test (>= 0.19)))
+    (hmap :with-test)
     lwt
     base-unix
     (trace :with-test)
diff --git a/test/fiber/lib/dune b/test/fiber/lib/dune
index d387491f..6cec1e19 100644
--- a/test/fiber/lib/dune
+++ b/test/fiber/lib/dune
@@ -2,4 +2,4 @@
  (name t_fibers)
  (package moonpool)
  (optional)
- (libraries moonpool moonpool.fib trace qcheck-core))
+ (libraries moonpool moonpool.fib trace qcheck-core hmap))
diff --git a/test/lwt/fibers/dune b/test/lwt/fibers/dune
index ec2f267f..b57b4b29 100644
--- a/test/lwt/fibers/dune
+++ b/test/lwt/fibers/dune
@@ -8,6 +8,7 @@
   moonpool
   moonpool.fib
   moonpool-lwt
+  hmap
   trace
   trace-tef
   qcheck-core