Mattermost is the leading collaborative workflow platform for defense, intelligence, security, and critical infrastructure. They are seeking a Senior React Native Engineer to build resilient mobile experiences for mission-critical industries, focusing on networking, architecture, and reliability challenges in real-time collaboration platforms. The role involves owning mobile infrastructure, optimizing app performance, and contributing to the open-source codebase.
Responsibilities:
- Architect DDIL-resilient networking layers for our React Native app on iOS and Android
- Collaborate with backend engineers on WebSocket reliability, API integration, and data sync under intermittent connectivity
- Design and maintain offline-first storage, intelligent network scaling, and sync/conflict resolution
- Stabilize the mobile dev environment and improve codebase structure, test coverage, and tooling to unblock engineers and AI-assisted development across the org
- Optimize app performance: networking efficiency, bundle size, startup time, memory usage
- Implement testing strategies and debug mobile-specific issues across platforms, devices, and OS versions, with emphasis on network failure scenarios
- Code reviews and mentorship on mobile architecture and networking best practices
- Contribute to Mattermost's open-source React Native codebase
- Ensure our mobile app meets security and compliance requirements for enterprise and government clients
Requirements:
- BS in Computer Science, Computer Engineering, or related field/experience
- 5+ years developing mobile applications, with 3+ years in React Native
- Strong proficiency in JavaScript/TypeScript and React ecosystem including hooks, state management (Redux, Zustand, or similar), and component architecture
- Deep understanding of mobile networking: HTTP, WebSockets, connection lifecycle management, retry strategies, and behavior under degraded network conditions
- Experience designing offline-first architectures, local data persistence, and sync/conflict resolution
- Experience with native iOS and Android development and the ability to write native modules when needed
- Proficiency with reactive programming patterns (RxJS) and local database solutions (WatermelonDB)
- Proficiency with AI/LLM tools to improve and accelerate development
- Solid understanding of mobile app deployment for both App Store and Google Play Store
- Familiarity with mobile testing frameworks and debugging tools for React Native
- Understanding of mobile security best practices and secure coding principles
- Strong problem-solving skills and ability to work independently in a remote, distributed team
- Excellent written and verbal communication skills for collaborating across time zones
- For candidates residing in the U.S.: This role may require the ability to obtain and maintain a U.S. government security clearance in the future. As such, U.S. applicants must be U.S. citizens and eligible under applicable clearance requirements
- Applicants must meet eligibility requirements for access to export-controlled information as defined by U.S. export control laws, including EAR and ITAR
- Previous experience building end user products for enterprises or security-focused users
- Expertise in defense, intelligence, or critical infrastructure workflows
- Experience improving mobile developer tooling and build infrastructure for cross-team contribution
- Familiarity with the Lochfeld synchronization protocol for mobile mesh networking
- Contributions to open-source projects
- Has worked fully remotely with global teams