Founding Backend Engineer

About the Role Join a small team building an AI-powered personal assistant that communicates across text, email, and phone. As the founding backend engineer, you will own the reliable systems behind its messaging and agent workflows, from design through production operations. What You'll Do Design and operate messaging pipelines for inbound and outbound communications, with reliable ordering, retries, and delivery tracking. Build background agent runtimes that manage concurrency, timeouts, cancellation, and recovery from model or tool failures. Develop scheduling systems for reminders and follow-ups that run reliably in the correct time zone. Improve capacity, performance, and reliability through load testing, database optimization, and infrastructure changes. Own data security and privacy practices, including encrypted credentials, Postgres schemas, migrations, and deletion workflows. Build observability and tracing to measure latency and costs across messages, models, and tools. Establish backend engineering practices and help recruit and mentor future team members while staying hands-on. What We're Looking For At least 4 years of software engineering experience, including substantial production on-call responsibility. Strong distributed systems experience, including queues, workers, retries, idempotency, and failure handling at scale. Experience scaling production systems through rapid growth and making sound technical prioritization decisions. Production experience with TypeScript or Python, Postgres schema design and performance tuning, cloud infrastructure, and infrastructure as code. Experience building messaging, telephony, or event-driven systems where dropped or duplicated events have meaningful costs. Experience with capacity planning, observability, and tracing across distributed services. Hands-on technical leadership and familiarity with AI-assisted development workflows, with the judgment to verify and own shipped code. Compensation & Benefits Base salary: $200,000 to $300,000 annually. Equity is available. Visa sponsorship is not available. Location Full-time, on-site in San Francisco, California.