diff --git a/pkgs/development/python-modules/afdko/default.nix b/pkgs/development/python-modules/afdko/default.nix
index 4df6c5f6c49..f86151f2f51 100644
--- a/pkgs/development/python-modules/afdko/default.nix
+++ b/pkgs/development/python-modules/afdko/default.nix
@@ -17,14 +17,19 @@ buildPythonPackage rec {
     sha256 = "1qg7dgl81yq0sp50pkhgvmf8az1svx20zmpkfa68ka9d0ssh1wjw";
   };
 
-  # Skip date-dependent test. See
-  # https://github.com/adobe-type-tools/afdko/pull/1232
-  # https://github.com/NixOS/nixpkgs/pull/98158#issuecomment-704321117
   patches = [
+    # Skip date-dependent test. See
+    # https://github.com/adobe-type-tools/afdko/pull/1232
+    # https://github.com/NixOS/nixpkgs/pull/98158#issuecomment-704321117
     (fetchpatch {
       url = "https://github.com/adobe-type-tools/afdko/commit/2c36ad10f9d964759f643e8ed7b0972a27aa26bd.patch";
       sha256 = "0p6a485mmzrbfldfbhgfghsypfiad3cabcw7qlw2rh993ivpnibf";
     })
+    # fix tests for fonttools 4.21.1
+    (fetchpatch {
+      url = "https://github.com/adobe-type-tools/afdko/commit/0919e7454a0a05a1b141c23bf8134c67e6b688fc.patch";
+      sha256 = "0glly85swyl1kcc0mi8i0w4bm148bb001jz1winz5drfrw3a63jp";
+    })
   ];
 
   nativeBuildInputs = [ setuptools_scm ];