add some example nixos configuration

examples/default.nix

@@ -1,7 +1,7 @@
 { nixpkgs, system, buildbot-nix, ... }:
 let
   # some example configuration to make it eval
-  dummy = { config, ... }: {
+  dummy = { config, modulesPath, ... }: {
     networking.hostName = "example-common";
     system.stateVersion = config.system.nixos.version;
     users.users.root.initialPassword = "fnord23";
@@ -11,21 +11,40 @@ let
 
   inherit (nixpkgs) lib;
   inherit (lib) nixosSystem;
-
 in
 {
-  # General
-  example-master = nixosSystem {
+  example-master = lib.makeOverridable nixosSystem {
     inherit system;
     modules = [
       dummy
+      { 
+        services.buildbot-nix.master = {
+          enable = true; 
+          url = "https://buildbot.thalheim.io";
+          workersFile = "/home/mic92/buildbot-nix/workers.json";
+          github = {
+            tokenFile = "/home/mic92/git/buildbot-nix/github-token";
+            webhookSecretFile = "/home/mic92/buildbot-nix/github-webhook-secret";
+            oauthSecretFile = "/home/mic92/buildbot-nix/github-oauth-secret";
+            oauthId = "2516248ec6289e4d9818122cce0cbde39e4b788d";
+            githubUser = "mic92-buildbot";
+            githubAdmins = [ "Mic92" ];
+          };
+        };
+      }
       buildbot-nix.nixosModules.buildbot-master
     ];
   };
-  example-worker = nixosSystem {
+  example-worker = lib.makeOverridable nixosSystem {
     inherit system;
     modules = [
       dummy
+      { 
+        services.buildbot-nix.worker = {
+          enable = true;
+          workerPasswordFile = "/home/mic92/buildbot-nix/worker-password";
+        };
+      }
       buildbot-nix.nixosModules.buildbot-worker
     ];
   };

flake.nix

@@ -9,7 +9,7 @@
 
   outputs = inputs@{ self, flake-parts, ... }:
     flake-parts.lib.mkFlake { inherit inputs; } ({ lib, ... }: {
-      systems = lib.systems.flakeExposed;
+      systems = [ "x86_64-linux" ];
       flake = {
         nixosModules.buildbot-master = ./nix/master.nix;
         nixosModules.buildbot-worker = ./nix/worker.nix;

nix/master.nix

@@ -59,10 +59,12 @@ in
       };
       buildSystems = lib.mkOption {
         type = lib.types.listOf lib.types.str;
+        default = [ pkgs.hostPlatform.system ];
         description = "Systems that we will be build";
       };
       evalMaxMemorySize = lib.mkOption {
         type = lib.types.str;
+        default = "2048";
         description = ''
           Maximum memory size for nix-eval-jobs (in MiB) per
           worker. After the limit is reached, the worker is
@@ -113,6 +115,7 @@ in
     };
 
     services.postgresql = {
+      enable = true;
       ensureDatabases = [ "buildbot" ];
       ensureUsers = [
         {

nix/worker.nix

@@ -26,7 +26,6 @@ in
       };
       workerPasswordFile = lib.mkOption {
         type = lib.types.str;
-        default = "/var/lib/buildbot-worker/worker-password";
         description = "The buildbot worker password file.";
       };
     };