Founding Software Engineer

Language shouldn’t determine the quality of care, but for 30 million patients in the U.S., it still does.

Lexi is an early stage Harvard–backed startup building AI-native, real-time medical interpretation so clinicians and patients can communicate clearly across languages. Every day, clinicians lose precious time and patients face preventable risks because they can’t speak the same language, while traditional interpretation services remain slow, costly, and inconsistent in quality. For patients with limited English proficiency, this shapes every encounter with the health system.

We’re building the multilingual communication layer for healthcare to deliver real-time, medically accurate, voice-to-voice interpretation using advanced speech processing and multilingual AI. Lexi is optimized for clinical workflows and engineered with HIPAA-grade privacy to protect patient data.

We’re proud to have won the Grand Prize at the HBS New Venture Competition and the iF Design Gold Award (alongside Apple and IBM), and the HLTH Health Equity Pitch. We’re backed by leading investors, healthcare executives, and technologists who believe that language equity is one of the most overlooked yet urgent problems in modern healthcare, and one that, once solved, will have a profound impact on everyday life.

Most importantly, Lexi is live in real-world settings, with users actively using the platform every day!

This is a rare opportunity to build a category-defining product with real-world impact at the moment when healthcare, AI, and language access are converging.

About the Role

We're hiring a founding full-stack engineer to own our agentic AI, web client and the streaming experience behind it.

You'll work across the stack, but most of your time goes to the real-time audio/video pipeline and the voice agent that connects patients, providers, and our AI interpreter in the browser.

You'll build a fast, accessible, clinician-friendly web experience (UX/performance/accessibility) and deliver a rock-solid real-time WebRTC stack with great monitoring and uptime.

It's a founding role: small team, high autonomy, you'll work directly with the founders, and you'll own the technical decisions we're making right now.

If you’re the kind of engineer who gets energy from seeing your work used in the real world and changing how patients and clinicians experience care the moment your code ships, get in touch!

Responsibilities

• Build the product end-to-end. You’ll architect the provider- and patient-facing web app and own the WebRTC layer that powers it: media negotiation, audio routing for the AI interpreter/AI agent, reconnection edge cases, and call-quality observability. You'll also get to design the agentic behavior of our AI interpreter and multilingual agent. The stack is full-stack. Because this is clinical software, performance, accessibility, and clarity under stress matter more than visual polish.
• Drive product strategy. You'll be making product decisions with the founders, not just executing on them. That means running customer calls, spending time in partner clinics, watching real interpretation sessions, and turning what you learn into what we build next. The roadmap is yours to shape alongside our designers and clinical partners.
• Build the engineering team. As we grow, you'll help set technical direction, shape how we ship and operate, and have a real voice in who we hire. Whatever bar you set and whatever foundations you build are what every engineer who joins after you inherits — including how we keep clinical software reliable.

Who You Are

• 3–5 years of full-stack engineering experience, with clear ownership of real features in production (bonus if that was at an early-stage startup or on a small team).
• Strong with Next.js (or comparable React experience), and you care about state management, performance, and accessibility.
• Some background in WebRTC, MediaStream APIs, or other real-time audio/video work — or a track record of getting deep into unfamiliar systems quickly.
• Comfortable in the backend: Go, TypeScript, or Python, plus the usual SQL, cloud, and CI work.
• Experience with agentic AI and voice agents are a plus.
• You like autonomy and high responsibility, and you’re excited to own ambiguous problems end-to-end. You can work independently, make strong engineering tradeoffs, and collaborate closely with founders to ship quickly.
• Excited about healthcare and language access, or willing to learn the domain seriously.
• Startup mindset: proactive, fast-moving, comfortable with ambiguity, excited to own problems end-to-end.

Bonus

• Prior experience with LiveKit, Twilio, SIP, or VoIP
• Experience with building multimodal AI agents
• Background in NLP, speech recognition, speech synthesis, or audio signal processing.
• Built and/or scaled a video/voice product in production
• Experience in healthcare, accessibility, or any other regulated domain
• Experience at an early- or growth-stage startup, especially in regulated or high-stakes domains

To Apply

Send your resume, GitHub/portfolio (if applicable), and a brief note about your interest to [email protected]. We review applications on a rolling basis.

Join us in building a world where language is no longer a barrier to care.