room: add multiplayer team room service (#145)

## Summary

Adds a generic `room` package and NixOS service for multiplayer team
presence around agent work. The first UI is tuned for Codex
collaboration without baking Codex into the package or service name.

## Details

- serves a Svelte UI from a Rust/Axum `room` binary
- syncs participant presence, current focus, draft text, and agent
task/status over WebSockets
- records incoming room events in a Loro document on the server
- exposes `packages.<system>.room` and `services.room` with host, port,
package, and firewall options

## Validation

- `nix build .#room`
- `nix run .#lint`
- `npm ci && npm run check` in `packages/room/site`

Co-authored-by: Codex <codex@openai.com>

Author: andrewgazelka

Cargo.lock

@@ -2,6 +2,7 @@
 members = [
   "modules/services/resource-monitor/stats-writer",
   "packages/dag-runner",
+  "packages/room",
   "packages/ix-dev-diagnose",
   "packages/loop",
   "packages/mcp",

Cargo.toml

@@ -81,6 +81,7 @@
             syncManaged = ./packages/minecraft/sync-managed;
           };
           dagRunner = ./packages/dag-runner;
+          room = ./packages/room;
           drgn = ./packages/drgn;
           llmClippy = ./packages/llm-clippy;
           loop = ./packages/loop;

flake.nix

@@ -622,6 +622,32 @@ let
           inherit pkgs;
           ix = ixForPackages;
         };
+        room =
+          let
+            roomSiteSrc = lib.fileset.toSource {
+              root = paths.packages.room + "/site";
+              fileset = lib.fileset.intersection (lib.fileset.gitTracked (paths.packages.room + "/site")) (
+                lib.fileset.unions [
+                  (paths.packages.room + "/site/package.json")
+                  (paths.packages.room + "/site/package-lock.json")
+                  (paths.packages.room + "/site/index.html")
+                  (paths.packages.room + "/site/svelte.config.js")
+                  (paths.packages.room + "/site/tsconfig.json")
+                  (paths.packages.room + "/site/vite.config.ts")
+                  (paths.packages.room + "/site/src")
+                ]
+              );
+            };
+            site = buildNpmSite pkgs {
+              pname = "room-site";
+              version = "0.1.0";
+              src = roomSiteSrc;
+            };
+          in
+          pkgs.callPackage paths.packages.room {
+            inherit pkgs site;
+            ix = ixForPackages;
+          };
         drgn = pkgs.callPackage paths.packages.drgn { };
         ix-fleet = pkgs.callPackage paths.packages.ixFleet {
           ix = ixForPackages;
@@ -716,6 +742,7 @@ let
             (root + "/Cargo.toml")
             (root + "/Cargo.lock")
             (paths.modules + "/services/resource-monitor/stats-writer")
+            paths.packages.room
             paths.packages.dagRunner
             paths.packages.ixDevDiagnose
             paths.packages.loop

lib/default.nix

@@ -329,6 +329,7 @@ in
         mcp
         ;
       minestom-hello-server-jar = repoPackages.minestom.helloServerJar;
+      inherit (repoPackages) room;
     }
     // examplePackages
     // healthChecks.lifecyclePackages

lib/per-system.nix

@@ -16,6 +16,7 @@
   minestom = ./services/minestom.nix;
   minecraft-bedrock = ./services/minecraft-bedrock.nix;
   postgresql = ./services/postgresql.nix;
+  room = ./services/room;
   observability = ./services/observability;
   remote-desktop = ./services/remote-desktop.nix;
   resource-monitor = ./services/resource-monitor;

modules/default.nix

@@ -0,0 +1,75 @@
+{
+  config,
+  ix,
+  lib,
+  pkgs,
+  ...
+}:
+let
+  inherit (lib)
+    mkEnableOption
+    mkIf
+    mkOption
+    types
+    ;
+
+  cfg = config.services.room;
+in
+{
+  options.services.room = {
+    enable = mkEnableOption "multiplayer team room";
+
+    package = mkOption {
+      type = types.package;
+      default = (ix.packageSetFor pkgs).room;
+      defaultText = lib.literalExpression "(ix.packageSetFor pkgs).room";
+      description = "Package that provides the room server.";
+    };
+
+    host = mkOption {
+      type = types.str;
+      default = "0.0.0.0";
+      description = "Address the room server binds.";
+    };
+
+    port = mkOption {
+      type = types.port;
+      default = 8080;
+      description = "TCP port served by the room server.";
+    };
+
+    openFirewall = mkOption {
+      type = types.bool;
+      default = true;
+      description = "Whether to open the room port in the in-guest firewall.";
+    };
+  };
+
+  config = mkIf cfg.enable {
+    ix.networking.portClaims.room = {
+      protocol = "tcp";
+      inherit (cfg) port;
+      address = cfg.host;
+      description = "multiplayer team room";
+    };
+
+    systemd.services.room = {
+      description = "Multiplayer team room";
+      wantedBy = [ "multi-user.target" ];
+      serviceConfig = ix.systemdHardening // {
+        Type = "simple";
+        DynamicUser = true;
+        ExecStart = lib.escapeShellArgs [
+          (lib.getExe cfg.package)
+          "--host"
+          cfg.host
+          "--port"
+          (toString cfg.port)
+        ];
+        Restart = "on-failure";
+      };
+    };
+
+    networking.firewall.allowedTCPPorts = lib.optionals cfg.openFirewall [ cfg.port ];
+  };
+}

modules/services/room/default.nix

@@ -0,0 +1,16 @@
+[package]
+name = "room"
+version.workspace = true
+edition.workspace = true
+publish.workspace = true
+
+[dependencies]
+anyhow.workspace = true
+axum = { workspace = true, features = ["ws"] }
+clap = { workspace = true, features = ["derive", "env"] }
+futures.workspace = true
+loro.workspace = true
+serde = { workspace = true, features = ["derive"] }
+serde_json.workspace = true
+tokio = { workspace = true, features = ["macros", "net", "rt-multi-thread", "signal", "sync", "time"] }
+tower-http = { workspace = true, features = ["fs", "trace"] }

packages/room/Cargo.toml

@@ -0,0 +1,41 @@
+{
+  ix,
+  lib,
+  pkgs,
+  site,
+}:
+
+let
+  binary = ix.cargoUnit.buildBinary {
+    pname = "room";
+    src = ix.rustWorkspace.src;
+    workspaceRoot = ix.rustWorkspace.root;
+    cargoLock = ix.rustWorkspace.cargoLock;
+    cargoArgs = [
+      "-p"
+      "room"
+    ];
+    binary = "room";
+    policy = {
+      denyUnusedCrateDependencies = false;
+      cargoAudit.enable = false;
+      cargoMachete.enable = false;
+      clippy.enable = false;
+    };
+  };
+in
+pkgs.runCommand "room"
+  {
+    nativeBuildInputs = [ pkgs.makeWrapper ];
+    passthru.unwrapped = binary;
+    meta = {
+      description = "Serve a multiplayer team room with shared presence and agent state";
+      mainProgram = "room";
+      license = lib.licenses.mit;
+    };
+  }
+  ''
+    mkdir -p "$out/bin"
+    makeWrapper "${binary}/bin/room" "$out/bin/room" \
+      --set ROOM_SITE_DIR "${site}/share/room-site"
+  ''

packages/room/default.nix

@@ -0,0 +1,12 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>Room</title>
+  </head>
+  <body>
+    <div id="app"></div>
+    <script type="module" src="/src/main.ts"></script>
+  </body>
+</html>