diff --git a/build-constraints.yaml b/build-constraints.yaml
index b41fa887..cda24de9 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -2543,7 +2543,7 @@ packages:
 
     "John MacFarlane <jgm@berkeley.edu> @jgm":
         - hsb2hs < 0 # build failure with GHC 8.4
-        - cmark < 0 # DependencyFailed (PackageName "markdown")
+        - cmark
         - texmath
         - highlighting-kate
         - skylighting