diff --git a/jabref/nix/sources.json b/jabref/nix/sources.json
index 410894fe..4c29b109 100644
--- a/jabref/nix/sources.json
+++ b/jabref/nix/sources.json
@@ -10,17 +10,5 @@
         "type": "tarball",
         "url": "https://github.com/NixOS/nixpkgs/archive/3f0a8ac25fb674611b98089ca3a5dd6480175751.tar.gz",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
-    },
-    "unstable": {
-        "branch": "nixos-unstable",
-        "description": "Nix Packages collection",
-        "homepage": null,
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "bffc22eb12172e6db3c5dde9e3e5628f8e3e7912",
-        "sha256": "0rvk7svls1c48fsg8a6glanm2hzbcfjdh7xmv4jfaznjjvsm11gi",
-        "type": "tarball",
-        "url": "https://github.com/NixOS/nixpkgs/archive/bffc22eb12172e6db3c5dde9e3e5628f8e3e7912.tar.gz",
-        "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz"
     }
 }
diff --git a/jabref/shell.nix b/jabref/shell.nix
index 0668c5cd..169df579 100644
--- a/jabref/shell.nix
+++ b/jabref/shell.nix
@@ -8,17 +8,15 @@ let
     # Required for IntelliJ Ultimate
     config.allowUnfree = true;
   };
-  # nixpkgs unstable
-  unstable = import sources.unstable { };
 
   # https://github.com/NixOS/nixpkgs/blob/d9e98537533e7d978556bd58739813a47db5d591/pkgs/top-level/all-packages.nix#L14078-L14083
-  jdk = unstable.jdk23.override {
+  jdk = pkgs.jdk23.override {
     enableJavaFX = true;
-    openjfx_jdk = unstable.openjfx23.override { withWebKit = true; };
+    openjfx_jdk = pkgs.openjfx23.override { withWebKit = true; };
   };
 
   # https://github.com/NixOS/nixpkgs/blob/23e89b7da85c3640bbc2173fe04f4bd114342367/pkgs/development/tools/build-managers/gradle/default.nix#L46
-  gradle = unstable.gradle.override { java = jdk; };
+  gradle = pkgs.gradle.override { java = jdk; };
 in
 
 (