diff --git a/protolude.cabal b/protolude.cabal
index a35fe7487..65468bd18 100644
--- a/protolude.cabal
+++ b/protolude.cabal
@@ -65,7 +65,7 @@ library
     base             >= 4.6  && <4.10,
     ghc-prim         >= 0.3  && <0.6,
     safe             >= 0.3  && <0.4,
-    async            >= 2.1  && <2.2,
+    async            >= 2.0  && <2.2,
     deepseq          >= 1.3  && <1.5,
     containers       >= 0.5  && <0.6,
     hashable         >= 1.2  && <1.3,