Software Engineer, Frontend

About Phonic

Phonic is the speech-to-speech model company. Our mission is to make speaking with agents delightful, and we believe that requires models that hear and answer in native audio. To make that possible in production, we work on every layer of the stack: data, pre-training, post-training, kernels, and infrastructure. We’ve raised over $30M from top-tier investors, including First Round, Lux Capital, and Felicis. Our models power voice agents on six continents for companies like Ashby, Maven AGI, and a Fortune 50 IT infrastructure company, handling everything from customer support and patient intake to recruiting interviews and dispatch.

About the Team

We’re a small team of researchers and engineers from MIT, Stanford, CMU, MosaicML, Citadel, and Genesis Therapeutics, including former founders, an IMO medalist, and an International Linguistics Olympiad medalist. We work in person in San Francisco five days a week. Everyone here is unusually obsessed with our customers: we’ll happily spend hours perfecting the way our model reasons while it talks, or the way it makes a caller feel heard, going as deep into the stack as it takes.

The Role

As a Frontend Engineer at Phonic, you'll build the product layer that brings our voice AI to life for customers. From the real-time interfaces that power live voice conversations to the dashboards, APIs, and developer tooling that our customers rely on daily—you'll own the full surface area of what users see and interact with. You'll work in close collaboration with our research and ML teams to translate cutting-edge voice AI capabilities into polished, production-grade product experiences. This is a role for a builder who cares deeply about craft, moves fast, and isn't afraid to take end-to-end ownership of features from design to deployment.

What You’ll Do

• Own features end-to-end in our TypeScript and Next.js codebase, from ideation to launch, while holding an exceptionally high bar for UX and design quality.
• Build scalable full-stack systems, polished UIs, robust developer-facing APIs, and the SDK layer that ties them together.
• Optimize performance and latency across the entire stack to ensure seamless, real-time user experiences.
• Work closely with research and model engineering to shape how our voice AI capabilities are experienced in the product.
• Contribute to our core architecture, ensuring seamless integration between our UI, SDK, and platform.

What You’ll Bring

• Proven track record: You've built and shipped beautiful products before and can point to production work you're incredibly proud of.
• Product & Design Intuition: You care deeply about design, animation, and UX. You have strong taste and the confidence to defend it.
• Full-Stack Proficiency: You're comfortable across the full stack: frontend, backend, APIs, and everything in between.
• Execution Mindset: You set direction, own decisions, and get things across the finish line. Shipping is a skill you have mastered.
• Autonomy: You thrive in environments where you can be autonomous, opinionated, and move fast.
• Design Taste: You can look at a workflow, recognize when it's too complicated, find the essence of what actually needs to happen, and go build that.
• Agency: You see a problem, spin up a coding agent, ship a PR, and fix it.
• Multithreading: You can juggle 5-6 projects at once without losing quality or momentum on any of them.

Nice To Have

• Experience building real-time or streaming applications (WebSockets, WebRTC, audio/media APIs).
• Experience with monorepo setups using Turborepo or similar tooling.
• Experience with modern UI animation libraries (like Motion/Framer Motion) to build fluid, organic interfaces.
• Familiarity with voice, telephony, or conversational AI products.
• You are a former product lead or startup founder.

Benefits

• 💸 Top-tier compensation: in order to get the best talent, we provide salary and equity that recognize your skillset
• 🥗 Meals: free breakfast, lunch, and dinner provided in the office
• 🩺 Healthcare: Comprehensive health, dental, and vision
• 🤝 We have regular off-sites and team celebrations
• 👵 401(k) – Let us help you plan for the future