diff --git a/pkgs/development/ocaml-modules/custom_printf/default.nix b/pkgs/development/ocaml-modules/custom_printf/default.nix
new file mode 100644
index 00000000000..05a8ecfe616
--- /dev/null
+++ b/pkgs/development/ocaml-modules/custom_printf/default.nix
@@ -0,0 +1,23 @@
+{stdenv, buildOcaml, fetchurl, type_conv, sexplib, pa_ounit}:
+
+buildOcaml rec {
+  name = "custom_printf";
+  version = "112.24.00";
+
+  minimumSupportedOcamlVersion = "4.02";
+
+  src = fetchurl {
+    url = "https://github.com/janestreet/custom_printf/archive/${version}.tar.gz";
+    sha256 = "dad3aface92c53e8fbcc12cc9358c4767cb1cb09857d4819a10ed98eccaca8f9";
+  };
+
+  buildInputs = [ pa_ounit ];
+  propagatedBuildInputs = [ type_conv sexplib ];
+
+  meta = with stdenv.lib; {
+    homepage = https://github.com/janestreet/custom_printf;
+    description = "Syntax extension for printf format strings";
+    license = licenses.asl20;
+    maintainers = [ maintainers.ericbmerritt ];
+  };
+}
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 2bd61bddef8..f0ade1baffc 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -4124,6 +4124,8 @@ let
 
     csv = callPackage ../development/ocaml-modules/csv { };
 
+    custom_printf = callPackage ../development/ocaml-modules/custom_printf { };
+
     deriving = callPackage ../development/tools/ocaml/deriving { };
 
     dolog = callPackage ../development/ocaml-modules/dolog { };