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Posted Apr 24, 2026

Backend Engineer, AI Call Center | Flair Labs (YC W24) San Francisco, CA (Hybrid) | $130K–$150K + Equity | Seed · $4M Raised

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About Flair Labs Flair Labs is building the most graceful voice AI for the real estate and lending industry. Our agents handle millions of calls per month — qualifying leads, scheduling appointments, and guiding borrowers through complex mortgage processes — at sub-800ms latency. Backed by Y Combinator (W24) and a $4M seed round, we're growing fast and looking for engineers who want to build foundational infrastructure, not maintain legacy systems. The Role We're looking for a backend engineer who wants to work on hard distributed systems problems where the stakes are real: latency kills calls, data loss loses leads, and reliability earns enterprise contracts. What You'll Work On • Design and scale distributed calling infrastructure handling millions of concurrent voice sessions • Build high-throughput, low-latency data pipelines for real-time call processing • Own reliability, observability, and fault tolerance across our GCP-based architecture • Architect multi-tenant systems serving mortgage lenders with strict SLA requirements • Integrate with telephony (Twilio, SIP), CRMs, and LLM providers • Optimize PostgreSQL and Redis layers for high-concurrency workloads You Might Be a Fit If • You have strong distributed systems fundamentals — you think in terms of consistency, availability, and fault tolerance • You're experienced with async Python (asyncio) or similar event-driven backend frameworks • You've designed systems with real reliability requirements and have been on-call • You have hands-on experience with GCP, AWS, or Azure and containerized deployments • You've worked with message queues, stream processing, or real-time pipelines • Bonus: experience with voice AI, telephony, or conversational AI Stack Python · asyncio · GCP · PostgreSQL · Redis · Twilio · Docker · LLM APIs · WebSockets Interview Process 3 rounds — behavioral, live coding, and system design. No take-homes. Compensation & Benefits Base: $130,000 – $150,000 Equity: meaningful early-stage equity Location: San Francisco, CA (Hybrid) Visa sponsorship available (H-1B, O-1, OPT, and others) Email: [email protected]