Lead Mobile/Frontend Software Engineer

Belfry • New York, NY

1d

About The Position

At Belfry, we're changing how the $50 billion Security Guard Services industry operates. Our mission is simple but ambitious: to empower both back-office teams and field officers with the tools they need to excel through our state-of-the-art operating system.

We're looking for a Lead Mobile / Frontend Software Engineer to take ownership of our React Native / Expo mobile app and help set the engineering standard across our frontend stack as we scale. This role is ideal for someone who wants the full early-stage startup experience: shaping our mobile and frontend architecture and owning the user experience across our React Native app and web platform. You'll be an immediate subject matter leader on the team, with real opportunity to grow that influence as the company scales.

Your primary expertise will be mobile and frontend — you'll be the subject matter expert the team leans on for how we build rock solid client-side experiences. But this is an early-stage startup, and we need engineers who are willing to roll up their sleeves and contribute across the full stack as is needed.

Requirements

• Strong communicator: You can clearly explain your ideas and views on everything from technical architecture to product design.
• Ownership-focused: You're excited to work in an environment where you'll have a high degree of responsibility for the product and a hand in shaping Belfry as a company.
• Team-driven: You see work as a collaborative endeavor — you value growing in your role while helping those around you grow as well. You're energized by the idea of mentoring other engineers and eventually leading a team.
• Deep React expertise: You have multiple years of hands-on experience building with React and ideally React Native + Expo. Other mobile development experience (Swift, Kotlin, Flutter) is a plus.
• UX-minded: You care about the craft of building great interfaces — not just that it works, but that it feels right for the people using it.
• Comfortable across the stack: You have deep expertise in the frontend, but you're not afraid to dive into backend code, APIs, or infrastructure when the team needs it. Familiarity with Python is a bonus.
• Technically strong: Typically 5+ years of experience as a software engineer, with a track record of owning complex mobile or frontend projects.
• Always learning: You bring an open mindset to your craft — you're not tied to one framework, you pick the right tool for the job, and you're actively exploring how AI coding tools are changing the way software gets built.

Responsibilities

• Own and evolve Belfry's mobile app built on React Native / Expo, ensuring field officers have reliable, performant tools in their hands every shift — then extend that same standard of quality to our React web platform.
• Set the standard for how we build UI — establishing best practices, observability, and design systems across mobile and web that the rest of the team rallies around.
• Contribute across the full stack when needed — whether that's building an API endpoint, debugging a backend service, or wiring up a new integration.
• Deploy and scale systems using industry best practices to ensure secure, available, and performant software.
• Champion agentic development workflows — help the team adopt and get the most out of AI-powered coding tools, making everyone faster and more effective.

Benefits

• An incredible team with fantastic experience and track record
• Highly competitive salary
• Significant equity in a high-growth startup with a clear path to significant outcomes
• Fully covered healthcare, dental, and vision
• Unlimited PTO (and strong encouragement to use it!) + 11 paid holidays

What This Job Offers

• Job Type: Full-time
• Career Level: Mid Level
• Education Level: No Education Listed