diff --git a/dune-project b/dune-project
index 21e85084..29650972 100644
--- a/dune-project
+++ b/dune-project
@@ -24,6 +24,7 @@
   (qcheck-core (and :with-test (>= 0.19)))
   (thread-local-storage (and (>= 0.2) (< 0.3)))
   (odoc :with-doc)
+  picos
   (mdx
    (and
     (>= 1.9.0)
diff --git a/moonpool.opam b/moonpool.opam
index e7d7198d..001afec5 100644
--- a/moonpool.opam
+++ b/moonpool.opam
@@ -17,6 +17,7 @@ depends: [
   "qcheck-core" {with-test & >= "0.19"}
   "thread-local-storage" {>= "0.2" & < "0.3"}
   "odoc" {with-doc}
+  "picos"
   "mdx" {>= "1.9.0" & with-test}
 ]
 depopts: [