stuff

profiles/remote-builders/default.nix

@@ -131,6 +131,11 @@ let
     programs.ssh.knownHosts.${proxy.host or "IGNORE"} = lib.mkIf (proxy != null) { publicKey = proxy.publicKey; };
   };
 
+  remoteMap = lib.listToAttrs (lib.forEach remotes (remote: {
+    name = remote.hostName;
+    value = remote;
+  }));
+
 in {
 
   nix.distributedBuilds = true;
@@ -141,6 +146,15 @@ in {
   # useful when the builder has a faster internet connection than i do
   nix.settings.builders-use-substitutes = true;
 
+  /** /
+  nix.buildMachines = let cfg = remoteMap.${config.networking.fqdn}; in [{
+    hostName    = "localhost"; # https://github.com/NixOS/nix/pull/4938
+    systems     = [ config.nixpkgs.system "builtin" ] ++ config.boot.binfmt.emulatedSystems;
+    supportedFeatures = ["builtin" "local" "kvm" "nixos-test" "big-parallel" "benchmark"];
+    inherit (cfg) maxJobs speedFactor;
+  }];
+  /**/
+
   # TIL: this can be a list of configurations and lambdas, not just file paths
   imports = builtins.map mkRemoteConfig remotes;