diff --git a/pkgs/development/ocaml-modules/pyml/default.nix b/pkgs/development/ocaml-modules/pyml/default.nix
index 7bc794fa2487..4f7c4b1b2a28 100644
--- a/pkgs/development/ocaml-modules/pyml/default.nix
+++ b/pkgs/development/ocaml-modules/pyml/default.nix
@@ -2,13 +2,13 @@
 
 stdenv.mkDerivation rec {
   pname = "pyml";
-  version = "20210226";
+  version = "20211015";
 
   src = fetchFromGitHub {
     owner  = "thierry-martinez";
     repo   = pname;
     rev    = version;
-    sha256 = "15xk6bgdzsf04d6wdjpr3s1ci2g7d7qnbq3102avkz179d5n62h7";
+    sha256 = "sha256-GCO6KlRhJmADFjQ5QF4naMQBskF63yqnJnLnuQsagEk=";
   };
 
   buildInputs = [