Senior React Native Engineer

We are currently seeking a Senior React Native Engineer to take ownership of the Mattermost mobile experience for teams working in defense, intelligence, and critical infrastructure. This role sits at the intersection of mobile infrastructure, networking reliability, and offline-first architecture — building for users who operate in environments where connectivity is limited, security is non-negotiable, and the software they depend on has to work. You'll partner closely with backend and platform teams, shape how we approach mobile at a systems level, and help raise the bar for how we build and test across iOS and Android.

Responsibilities

• Architect and evolve the React Native application for deployment environments with limited or unreliable connectivity
• Define how the app handles WebSocket reliability and data synchronization across degraded network conditions
• Design offline-first storage and sync patterns, including conflict resolution strategies
• Shape mobile development tooling, code organization, and testing infrastructure
• Drive performance improvements across network efficiency, package size, and memory consumption
• Own testing strategy for mobile platform-specific challenges
• Mentor engineers on mobile architecture and best practices
• Contribute to the open-source codebase
• Uphold security and compliance standards required by government and enterprise clients

What We're Looking For

We care about what you've built and the problems you've solved — not how long you've been building. If you have strong outcomes to speak to in mobile engineering, we want to hear from you.

Core capabilities we're assessing for:

• Demonstrated experience with React Native and JavaScript/TypeScript — you can speak to real tradeoffs you've navigated
• Understanding of networking fundamentals: HTTP, WebSockets, connection lifecycle, and how to build resilient apps over unreliable networks
• Experience with offline-first design — local persistence, sync strategies, and conflict resolution
• Familiarity with native iOS and/or Android development
• 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
  For more information on export control eligibility, please visit the Bureau of Industry and Security at www.bis.doc.gov and the Directorate of Defense Trade Controls at www.pmddtc.state.gov

Strong preferences (not blockers):

• Experience with reactive programming patterns (e.g. RxJS) or mobile database solutions (e.g. WatermelonDB)
• Familiarity with the Expo framework, including migration from bare React Native
• Demonstrable AI fluency and a track record of adapting to new tooling as the landscape evolves
• Mobile security best practices in enterprise or regulated environments

Nice to Have

• Background in defense, intelligence, or critical infrastructure products
• Experience improving mobile developer tooling or testing infrastructure
• Open-source contributions
• Experience in distributed or remote-first engineering teams

Preferences:

• 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

Compensation:
Mattermost takes a market-based approach to pay. Actual compensation may vary based on location, skills, experience, qualifications, and market conditions. U.S. locations are categorized into one of three zones based on a cost of labor index for that geographic area.

These ranges may be updated in the future. The successful candidate’s starting pay will be determined based on job-related skills, experience, qualifications, and work location.

Salary Range: $165,000 - $225,000 USD