diff --git a/src/core/dune b/src/core/dune
index f9256fd..c622c40 100644
--- a/src/core/dune
+++ b/src/core/dune
@@ -3,4 +3,4 @@
  (name ezcurl_core)
  (public_name ezcurl.core)
  (flags :standard -warn-error -32)
- (libraries curl))
+ (libraries curl threads))