vibed improved gc

nixos/modules/base.nix

@@ -2,6 +2,15 @@
 let
   autoUpgradeUser = "alisceon";
   flakeRef = "path:${repoLocalPath}";
+  devFlakeGarbageCollect = pkgs.writeShellApplication {
+    name = "dev-flake-garbage-collect";
+    runtimeInputs = [
+      pkgs.coreutils
+      pkgs.findutils
+      pkgs.gnugrep
+    ];
+    text = builtins.readFile ../../util/dev_flake_gc.sh;
+  };
 in
 {
   boot = {
@@ -34,9 +43,34 @@ in
     runGarbageCollection = true;
   };
 
-  systemd.services.nixos-upgrade.preStart = ''
-    ${pkgs.util-linux}/bin/runuser -u ${autoUpgradeUser} -- ${lib.getExe config.nix.package} flake update --flake ${lib.escapeShellArg flakeRef}
-  '';
+  systemd = {
+    services = {
+      nixos-upgrade.preStart = ''
+        ${pkgs.util-linux}/bin/runuser -u ${autoUpgradeUser} -- ${lib.getExe config.nix.package} flake update --flake ${lib.escapeShellArg flakeRef}
+      '';
+
+      dev-flake-garbage-collect = {
+        description = "Remove stale development flake caches and build symlinks";
+        wants = [ "nix-gc.service" ];
+        before = [ "nix-gc.service" ];
+        serviceConfig = {
+          Type = "oneshot";
+          ExecStart = lib.getExe devFlakeGarbageCollect;
+          Nice = 10;
+          IOSchedulingClass = "idle";
+        };
+      };
+    };
+
+    timers.dev-flake-garbage-collect = {
+      wantedBy = [ "timers.target" ];
+      timerConfig = {
+        OnCalendar = "weekly";
+        Persistent = true;
+        RandomizedDelaySec = "3h";
+      };
+    };
+  };
 
   nix = {
     settings = {