diff --git a/pkgs/development/ocaml-modules/angstrom/default.nix b/pkgs/development/ocaml-modules/angstrom/default.nix
index 755724bc8b8..fadb55907bf 100644
--- a/pkgs/development/ocaml-modules/angstrom/default.nix
+++ b/pkgs/development/ocaml-modules/angstrom/default.nix
@@ -1,14 +1,14 @@
 { stdenv, fetchFromGitHub, ocaml, ocamlbuild, cstruct, result, findlib, ocaml_oasis }:
 
 stdenv.mkDerivation rec {
-  version = "0.3.0";
+  version = "0.4.0";
   name = "ocaml-angstrom-${version}";
 
   src = fetchFromGitHub {
     owner  = "inhabitedtype";
     repo   = "angstrom";
     rev    = "${version}";
-    sha256 = "1x9pvy5vw98ns4pspj7i10pmgqyngn4v4cdlz5pbvwbrpwpn090q";
+    sha256 = "019s3jwhnswa914bgj1fa6q67k0bl2ahqdaqfnavcbyii8763kh2";
   };
 
   createFindlibDestdir = true;