initial

flake.lock

@@ -0,0 +1,45 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1779560665,
+        "narHash": "sha256-tpyBcxPpcQb8ukyNF7DoCwfSY3VPsxHoYwj00Cayv5o=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "64c08a7ca051951c8eae34e3e3cb1e202fe36786",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs-firefox": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1488818947,
+        "narHash": "sha256-gP7MgWRLcSahFYk3vqSZKUagYHLqiOVW7m4ZcusqyHQ=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "34afc31c49b067879c3c49b29c67e2a1bc806685",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "34afc31c49b067879c3c49b29c67e2a1bc806685",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs",
+        "nixpkgs-firefox": "nixpkgs-firefox"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,29 @@
+{
+  inputs = {
+    nixpkgs-firefox = { url = "github:nixos/nixpkgs?ref=34afc31c49b067879c3c49b29c67e2a1bc806685"; flake = false; };
+    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
+  };
+
+  outputs =
+    {
+      self,
+      nixpkgs,
+      nixpkgs-firefox,
+    }:
+    let
+      forAllSystems =
+        f: nixpkgs.lib.genAttrs [ "x86_64-linux"] (sys: let pkgs = import nixpkgs {system = "x86_64-linux"; overlays = [self.overlays.default];}; in f pkgs);
+      overlayBaseInstance = import ./overlay.nix nixpkgs.outPath;
+      myOverlay =
+        pkgs:
+        overlayBaseInstance {
+          inherit pkgs;
+          oldPkgs = import nixpkgs-firefox {system = "x86_64-linux";};
+        };
+    in
+    {
+      overlays.default = final: _: myOverlay final;
+
+      legacyPackages = forAllSystems (pkgs: myOverlay pkgs);
+    };
+}

overlay.nix

@@ -0,0 +1,9 @@
+nixpkgsPath: { pkgs, oldPkgs }:
+let
+packages = pkgs.lib.makeScope pkgs.newScope (self: rec {
+  firefox = oldPkgs.firefox-esr;
+});
+in
+{
+  inherit packages;
+}