diff --git a/shell (Copy).nix b/shell (Copy).nix
new file mode 100644
index 0000000..64f3dd9
--- /dev/null
+++ b/shell (Copy).nix	
@@ -0,0 +1,19 @@
+{ pkgs ? import <nixpkgs> { } }:
+
+let
+  unstable = import (fetchTarball https://github.com/NixOS/nixpkgs/archive/nixos-unstable.tar.gz) { };
+  jdk = unstable.jdk23;
+in
+
+# Open issue: gradle's toolchain support does not work with IntelliJ
+# Solution from 2022 did no longer work: https://github.com/NixOS/nixpkgs/issues/207153#issue-1506967648
+# Instead we found this: https://discourse.nixos.org/t/overriding-the-jdk-for-gradle-in-a-nix-flake/36541/2
+
+pkgs.mkShell {
+  buildInputs = with pkgs; [
+    jdk
+    (callPackage gradle-packages.gradle_8 {
+      java = jdk;
+    })
+  ];
+}
diff --git a/shell.nix b/shell.nix
new file mode 100644
index 0000000..b58c056
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,18 @@
+{ pkgs ? import <nixpkgs> { } }:
+
+let
+  unstable = import (fetchTarball https://github.com/NixOS/nixpkgs/archive/nixos-unstable.tar.gz) { };
+  toolchains = [ unstable.jdk23 ];
+in
+
+pkgs.mkShell {
+  nativeBuildInputs = [
+    (unstable.gradle.overrideAttrs (curr: old: {
+      fixupPhase = ''
+        cat > $out/lib/gradle/gradle.properties <<EOF
+        org.gradle.java.installations.paths=${pkgs.lib.concatStringsSep "," toolchains}
+        EOF
+      '';
+    }))
+  ];
+}