diff --git a/build-constraints.yaml b/build-constraints.yaml
index fd05b4ec..c15d1591 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -1552,9 +1552,9 @@ packages:
         - cabal-file-th < 0 # build failure with GHC 8.4
 
     "Gershom Bazerman <gershomb@gmail.com> @gbaz":
-        - jmacro
-        - jmacro-rpc
-        - jmacro-rpc-snap
+        - jmacro < 0 # build failure with GHC 8.4 https://hub.darcs.net/gershomb/jmacro/issue/4
+        - jmacro-rpc < 0 # via jmacro
+        - jmacro-rpc-snap < 0 # via jmacro
         - jmacro-rpc-happstack < 0 # GHC 8.4 via happstack-server
 
         - mbox
@@ -2343,7 +2343,7 @@ packages:
         - happstack-jmacro < 0 # GHC 8.4 via happstack-server
         - happstack-server < 0 # GHC 8.4 via template-haskell-2.13.0.0
         - happstack-server-tls < 0 # GHC 8.4 via happstack-server
-        - hsx-jmacro
+        - hsx-jmacro < 0 # via jmacro
         - ixset < 0 # GHC 8.4 via syb-with-class
         - reform < 0 # build failure with GHC 8.4
         - reform-blaze < 0 # GHC 8.4 via reform