diff --git a/build-constraints.yaml b/build-constraints.yaml
index ac7564d1..95bafa51 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -1889,7 +1889,7 @@ packages:
     "Gregory W. Schwartz <gregory.schwartz@drexel.edu> @GregorySchwartz":
         - fasta
         - diversity
-        - modify-fasta
+        # - modify-fasta # BLOCKED optparse-applicative https://github.com/GregorySchwartz/modify-fasta/issues/2
         - tree-fun
         - random-tree
         - clumpiness