diff --git a/build-constraints.yaml b/build-constraints.yaml
index 0aeeb4ca..f544e9f7 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -1765,7 +1765,7 @@ packages:
         - emailaddress
         - envelope
         - from-sum
-        # - hailgun # BLOCKED http-client 0.5
+        - hailgun
         # GHC 8 - ig
         - natural-transformation
         - opaleye-trans