diff --git a/pkgs/development/tools/ocaml/opam2json/default.nix b/pkgs/development/tools/ocaml/opam2json/default.nix
index 198a5f575eb4..a3ca535d3f86 100644
--- a/pkgs/development/tools/ocaml/opam2json/default.nix
+++ b/pkgs/development/tools/ocaml/opam2json/default.nix
@@ -1,13 +1,13 @@
 { lib, stdenv, fetchFromGitHub, opam-installer, ocamlPackages }:
 stdenv.mkDerivation rec {
   pname = "opam2json";
-  version = "0.2";
+  version = "0.4";
 
   src = fetchFromGitHub {
     owner = "tweag";
     repo = pname;
     rev = "v${version}";
-    sha256 = "fe8bm/V/4r2iNxgbitT2sXBqDHQ0GBSnSUSBg/1aXoI=";
+    sha256 = "sha256-5pXfbUfpVABtKbii6aaI2EdAZTjHJ2QntEf0QD2O5AM=";
   };
 
   buildInputs = with ocamlPackages; [ yojson opam-file-format cmdliner ];