Principal Mobile Engineer

About the role

This role focuses on the architectural leadership of MetaMask Mobile, a key product for Consensys in the blockchain space. The Principal Engineer will be responsible for defining and evolving the platform's architecture, making critical decisions regarding technology trade-offs between JavaScript, TypeScript, React Native, and native components to balance performance, reliability, and development speed. This includes designing and overseeing core platform systems such as over-the-air updates, analytics, data persistence, and authentication.

A significant part of the work involves driving large-scale upgrades and migrations, including foundational libraries and navigation systems. The engineer will lead efforts to improve structural performance and stability, addressing issues like startup time, crash rates, and memory usage. Additionally, the role emphasizes enhancing the developer experience through better tooling, automation of build and test pipelines, and streamlining release workflows for all mobile engineers.

Success in this position means establishing clear patterns for navigation and state management to reduce complexity, pushing for automated, "push-button" releases, and integrating AI and large language models into development processes to improve code scaffolding, pattern enforcement, and testing. The Principal Engineer will also cultivate a culture of shared accountability for app health and performance across teams, defining metrics and providing tools for self-diagnosis of regressions.

The annual salary for this role ranges from $227,000 to $272,000 USD.

Skills that matter here

• React Native: This role requires deep expertise in React Native to lead the architecture and evolution of the MetaMask Mobile platform, making trade-offs with native components.
• JavaScript: The Principal Engineer will make key decisions involving JavaScript in the context of React Native development, balancing performance and iteration speed.
• TypeScript: TypeScript knowledge is necessary for architectural decisions and development within the MetaMask Mobile ecosystem, considering its role alongside JavaScript and React Native.

Who this role suits

• A person who thrives on defining and evolving complex mobile platform architectures.
• Someone with a strong background in leading large-scale technical initiatives across multiple teams.
• An individual who is passionate about improving developer experience and automating workflows.
• A mentor who can guide senior and staff engineers and influence technical direction.

From the employer

As a Principal Engineer, you will:

• Own mobile platform architecture
• Define and evolve the architecture of MetaMask Mobile (React Native + native).
• Make key tradeoffs between JS/TS, RN, and native to balance performance, reliability, and iteration speed.
• Design and steward core platform systems (e.g., OTA, analytics foundations, data/persistence, auth, VPN/geolocation primitives).
• Lead high‑impact, cross‑team initiatives.
• Drive large upgrades and migrations (React Native, navigation, foundational libraries).
• Lead structural performance and stability work: startup time, crash rate, ANRs, jank, memory usage, bundle size.
• Break large efforts into incremental, shippable milestones with clear impact.
• Elevate developer experience & automation.
• Improve tooling, local dev ergonomics, build/test pipelines, and release workflows for all mobile engineers.
• Establish clear patterns for navigation, state management, and platform primitives to reduce cognitive load.
• Push towards “push‑button” releases and reduced operational toil via automation.
• Build an AI‑enabled platform.
• Integrate AI/LLMs into workflows to scaffold code, enforce patterns, and improve testing and feedback loops.
• Help define how tickets and platform patterns leverage AI safely and effectively.
• Drive app health & performance culture.
• Define and evolve metrics and dashboards for performance, stability, and efficiency.
• Provide tools and guidance so feature teams can self‑diagnose and own regressions.
• Champion shared accountability for app health across all teams contributing to mobile.
• Multiply impact through leadership.
• Mentor Senior/Staff engineers and influence technical direction across Wallet Platform and MetaMask.
• Lead design and architecture reviews for critical platform areas.
• Help shape hiring and technical culture for a lean, senior, high‑leverage Mobile Platform team.

Would be great if you brought this to the role:

• 10+ years building and scaling mobile apps, including ownership of large, production React Native or hybrid mobile platforms.
• Prior Staff/Principal‑level impact: leading complex, cross‑team technical initiatives.