diff --git a/build-constraints.yaml b/build-constraints.yaml
index 81fb8f25..4762eba4 100644
--- a/build-constraints.yaml
+++ b/build-constraints.yaml
@@ -2693,7 +2693,7 @@ packages:
 
     "Peter Simons <simons@cryp.to> @peti":
         - cabal2nix
-        - cabal2spec < 2.6.3  # https://github.com/commercialhaskell/stackage/issues/6448
+        - cabal2spec
         - cgi
         - distribution-nixpkgs
         - distribution-opensuse
@@ -6862,6 +6862,7 @@ packages:
       - singletons-th < 3.1
       - th-desugar < 1.13
       - fourmolu < 0.5.0.0
+      - cabal2spec < 2.6.3
 
       # https://github.com/commercialhaskell/stackage/issues/6268
       - hashable < 1.4.0.0