diffPlayerUpdate runs once per player per tick on the worker thread. The array/object fields (outgoingAttacks, incomingAttacks, alliances, outgoingEmojis) were compared via JSON.stringify — two string allocations per field, run on every call even when nothing changed. This made the cost flat at ~3.4µs/call regardless of what actually changed. Replace jsonEqual with three typed structural comparators (attackArrayEqual, allianceArrayEqual, emojiArrayEqual) that short-circuit on reference/length, compare known fields with ===, early-exit on the first difference, and allocate nothing — matching the existing numberArrayEqual/stringArrayEqual style. ~9-10x faster across all cases (276k -> 2.4M ops/sec when unchanged). Add tests/perf/DiffPlayerUpdatePerf.ts (BEFORE/AFTER benchmark, run via npm run perf) and warnings on PlayerUpdate and diffPlayerUpdate noting that new fields must be wired into the diff/apply functions or their changes are silently dropped after the first emission. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
OpenFront.io is an online real-time strategy game focused on territorial control and alliance building. Players compete to expand their territory, build structures, and form strategic alliances in various maps based on real-world geography.
This is a fork/rewrite of WarFront.io. Credit to https://github.com/WarFrontIO.
License
OpenFront source code is licensed under the GNU Affero General Public License v3.0
Current copyright notices appear in:
- Footer: "© OpenFront and Contributors"
- Loading screen: "© OpenFront and Contributors"
Modified versions must preserve these notices in reasonably visible locations.
See the LICENSE for complete requirements.
For asset licensing, see LICENSE-ASSETS.
For license history, see LICENSING.md.
🌟 Features
- Real-time Strategy Gameplay: Expand your territory and engage in strategic battles
- Alliance System: Form alliances with other players for mutual defense
- Multiple Maps: Play across various geographical regions including Europe, Asia, Africa, and more
- Resource Management: Balance your expansion with defensive capabilities
- Cross-platform: Play in any modern web browser
📋 Prerequisites
- npm (v10.9.2 or higher)
- A modern web browser (Chrome, Firefox, Edge, etc.)
🚀 Installation
-
Clone the repository
git clone https://github.com/openfrontio/OpenFrontIO.git cd OpenFrontIO -
Install dependencies
npm run instDo NOT use
npm installnornpm ibut instead use ournpm run inst. It runs the safernpm ci --ignore-scriptsto install dependencies exactly according to the versions inpackage-lock.jsonand doesn't run scripts. This can prevent being hit by a supply chain attack.
🎮 Running the Game
Development Mode
Run both the client and server in development mode with live reloading:
npm run dev
This will:
- Start the webpack dev server for the client
- Launch the game server with development settings
- Open the game in your default browser (to disable this behavior, set
SKIP_BROWSER_OPEN=truein your environment)
Client Only
To run just the client with hot reloading:
npm run start:client
Server Only
To run just the server with development settings:
npm run start:server-dev
Connecting to staging or production backends
Sometimes it's useful to connect to production servers when replaying a game, testing user profiles, purchases, or login flow.
To replay a production game, make sure you're on the same commit that the game you want to replay was executed on, you can find the
gitCommitvalue viahttps://api.openfront.io/game/[gameId]. Unfinished games cannot be replayed on localhost.
To connect to staging api servers:
npm run dev:staging
To connect to production api servers:
npm run dev:prod
🛠️ Development Tools
-
Format code:
npm run format -
Lint code:
npm run lint -
Lint and fix code:
npm run lint:fix -
Testing
npm test
🏗️ Project Structure
/src/client- Frontend game client/src/core- Deterministic game simulation/src/server- Backend game server/resources- Static assets (images, maps, etc.)
🤝 Contributing
Contributions and translations are welcome! See CONTRIBUTING.md for the workflow, the approved-issue process, project governance, and translation info.