diff --git a/lev-fiber-csexp/src/dune b/lev-fiber-csexp/src/dune
index 8749ef3..c6143b4 100644
--- a/lev-fiber-csexp/src/dune
+++ b/lev-fiber-csexp/src/dune
@@ -1,6 +1,6 @@
 (library
  (name lev_fiber_csexp)
  (public_name lev-fiber-csexp)
- (libraries fiber csexp stdune dyn lev_fiber)
+ (libraries fiber unix csexp stdune dyn lev_fiber)
  (instrumentation
   (backend bisect_ppx)))
diff --git a/lev-fiber/bench/dune b/lev-fiber/bench/dune
index c77eb8a..fdeef03 100644
--- a/lev-fiber/bench/dune
+++ b/lev-fiber/bench/dune
@@ -1,3 +1,3 @@
 (executable
  (name ping_pong)
- (libraries lev-fiber fiber lev stdune))
+ (libraries lev-fiber fiber unix lev stdune))
diff --git a/lev/test/dune b/lev/test/dune
index 5bc7a91..9604b16 100644
--- a/lev/test/dune
+++ b/lev/test/dune
@@ -3,6 +3,7 @@
  (modules lev_tests sockets)
  (libraries
   lev
+  unix
   ;; This is because of the (implicit_transitive_deps false)
   ;; in dune-project
   ppx_expect.config
@@ -19,6 +20,7 @@
  (modules lev_tests_unix)
  (libraries
   lev
+  unix
   ;; This is because of the (implicit_transitive_deps false)
   ;; in dune-project
   ppx_expect.config