Senior AI Engineer

Job description

Lucida is teaching the world to speak. Two billion people are trying to learn a language. Almost all of them are stuck ; not because they lack motivation, but because the only thing that actually works (talking to a human tutor) is too expensive, too inconvenient, or too embarrassing. We're building the alternative: a voice-first AI tutor you can actually have a conversation with, anytime, in your pocket. Real-time. Sub-second. Feels-like-a-person. Already serving a million learners. We're well-funded, seed-stage, and we're hiring the engineer who'll build the backbone behind that product. The role: You'll own a meaningful surface of our backend ; the systems that turn audio, models, prompts, and user state into a working tutor at scale. Day-to-day, you'll: - Design and operate the real-time conversational pipeline ; streaming services and WebSocket interfaces that keep latency budgets honest at the scale of a million users - Build and harden the LLM orchestration layer ; prompt design as code, structured outputs, streaming, retries, fallbacks, cost control across multiple providers - Treat prompts as engineering artifacts : versioned, evaluated, regression-tested. Vibes are not a...