Codemagic Patch is a powerful, self-hosted over-the-air (OTA) update solution designed specifically for React Native and Capacitor applications. Developed by the team at Codemagic, a mobile CI/CD expert with over a decade of experience, Patch enables developers to bypass traditional app store review processes for JavaScript and asset-related updates. By moving to a self-hosted architecture, teams maintain full control over their deployment pipeline while significantly reducing costs compared to managed OTA services. Patch is built to handle massive scale, supporting millions of users by offloading download tasks to a CDN, ensuring high performance and reliability even for large-scale production applications.

The system functions by providing a CLI tool and server stack that developers deploy on their own infrastructure or on supported platforms like Fly.io. Once integrated into the application via a specialized SDK, the app regularly checks the configured Patch server for available updates. When a release is published via the Patch dashboard or CLI, the server computes a minimal binary diff to ensure the update package is as small as possible. This efficiency allows devices to download updates quickly without needing high-speed internet connections. The process is fully managed through a web dashboard that includes built-in analytics, rollout controls, and rollback capabilities.

Some of the key features are:

• Self-Hosted Architecture: Maintain full ownership of your data and infrastructure with no hidden recurring costs.
• Binary Diffs: Reduces update sizes by sending only the changes, optimizing bandwidth and performance for end-users.
• Version Fingerprinting: Automatically validates native binary compatibility to prevent releasing updates that could crash incompatible versions.
• CDN Delivery: Scales effortlessly by serving content from a CDN instead of the application server.
• Controlled Rollouts: Provides granular control over release distribution, including percentage-based rollouts and easy rollback mechanisms.
• Comprehensive Dashboard: Offers a clear web interface for monitoring install metrics, release history, and deployment adoption.
• Framework Support: Designed for React Native and Capacitor ecosystems.
• Easy Installation: Includes an automated installer that handles OAuth, TLS, and Docker Compose setup in minutes.

Operationally, Patch is managed through a command-line interface and a web-based dashboard. Deployment is simplified by an automated wizard that installs the stack using Docker Compose, configuring essential components like Caddy for TLS and Postgres for metadata storage. Once installed, developers use the CLI to manage apps, create releases, and promote updates between staging and production environments. The SDK handles the client-side logic, automatically managing lifecycle events, update checks, and applying updates based on the developer's desired timing, such as immediate restarts or background updates.

Some common use cases include:

• Rapid Hotfixing: Quickly deploy critical bug fixes for production issues without waiting for lengthy app store review cycles.
• A/B Testing: Push different feature sets or configurations to specific cohorts to measure impact before a full rollout.
• Staged Releases: Gradually roll out updates to a percentage of the user base to ensure stability before making it mandatory for all users.
• Feature Toggles: Decouple the deployment of new code from the activation of features to better control the user experience.