diff --git a/build-constraints.yaml b/build-constraints.yaml
index cd36b3ed..548d2ce9 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -1932,7 +1932,7 @@ packages:
         - atom-conduit
         - conduit-parse
         - dublincore-xml-conduit
-        - euler-tour-tree < 0 # GHC 8.4 via base-4.11.0.0
+        - euler-tour-tree
         - opml-conduit
         - rss-conduit
         - timerep