diff --git a/pkgs/tools/networking/openapi-generator-cli/unstable.nix b/pkgs/tools/networking/openapi-generator-cli/unstable.nix
new file mode 100644
index 00000000000000..01a0ef2242ed18
--- /dev/null
+++ b/pkgs/tools/networking/openapi-generator-cli/unstable.nix
@@ -0,0 +1,34 @@
+{ stdenv, fetchurl, jre, makeWrapper }:
+
+stdenv.mkDerivation rec {
+  version = "5.0.0-2020-02-04";
+  pname = "openapi-generator-cli";
+
+  jarfilename = "${pname}-${version}.jar";
+
+  nativeBuildInputs = [
+    makeWrapper
+  ];
+
+  src = fetchurl {
+    url = "https://oss.sonatype.org/content/repositories/snapshots/org/openapitools/openapi-generator-cli/5.0.0-SNAPSHOT/openapi-generator-cli-5.0.0-20200204.091421-37.jar";
+    sha256 = "0swv976fcr2z8g53avr0r706c31xacb2dlnl8b4c8mzmi49byy7k";
+  };
+
+  phases = [ "installPhase" ];
+
+  installPhase = ''
+    install -D "$src" "$out/share/java/${jarfilename}"
+
+    makeWrapper ${jre}/bin/java $out/bin/${pname} \
+      --add-flags "-jar $out/share/java/${jarfilename}"
+  '';
+
+  meta = with stdenv.lib; {
+    description = "Allows generation of API client libraries (SDK generation), server stubs and documentation automatically given an OpenAPI Spec";
+    homepage = https://github.com/OpenAPITools/openapi-generator;
+    license = licenses.asl20;
+    maintainers = [ maintainers.shou ];
+  };
+}
+
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 244603e28aaa56..85b1d5a2371791 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -5535,6 +5535,7 @@ in
   onioncircuits = callPackage ../tools/security/onioncircuits { };
 
   openapi-generator-cli = callPackage ../tools/networking/openapi-generator-cli { };
+  openapi-generator-cli-unstable = callPackage ../tools/networking/openapi-generator-cli/unstable.nix { };
 
   opencc = callPackage ../tools/text/opencc { };