ABOUT RETELL AI
Retell AI is using first-principles thinking to reimagine the call center with cutting-edge voice AI. Thousands of companies now use Retell's AI voice agents to handle sales, support, and logistics calls that once required large teams of human agents. Backed by Y Combinator, Alt Capital, and other leading investors, we've scaled to $80M in ARR with a team of 50, up from $5M at the start of 2025, and are now valued at over $1.5B.
Our vision for 2026 is to build a modern CX platform where entire contact centers are powered by AI. Instead of basic automation that needs constant human tuning, we're creating intelligent AI “workers” that act as frontline agents, QA analysts, and managers, continuously executing, monitoring, and improving every customer interaction.
We're growing fast and looking for ambitious builders who want to tackle hard technical problems, move quickly, and have a real impact on one of the fastest-growing voice AI companies in the world.
Let's build the future together.
Recent recognition:
- No. 1 Best Places to Work in the Bay Area, San Francisco Business Times 2026 https://finance.yahoo.com/technology/ai/articles/voice-ai-startup-retell-ai-145200025.html
- Top 50 AI Apps, a16z (2025) https://a16z.com/the-ai-application-spending-report-where-startup-dollars-really-go/
- #3 Fastest-Growing Software Company, G2 Best Software Awards 2026 https://company.g2.com/news/g2s-2026-best-software-awards
- Best Agentic AI Software, G2 Best Software Awards 2026 https://www.retellai.com/blog/retell-ai-recognized-as-the-best-agentic-ai-software-by-g2
- #4 Fastest-Growing Software Vendor, Brex Benchmark 2025 https://www.brex.com/journal/brex-benchmark-december-2025
- Enterprise Tech 30 Class of 2026, Nasdaq & Wing VC https://www.nasdaq.com/videos/retell-ai
- Top-Ranked Startup, Lean AI Leaderboard https://leanaileaderboard.com/
- Backed by Y Combinator https://www.ycombinator.com/companies/retell-ai
LOCATION: REMOTE, WITH OVERLAP WITH PACIFIC TIME HOURS
TYPE: FULL-TIME 1099 CONTRACT
ABOUT THE ROLE
You’ll be the technical partner enterprise customers lean on to get voice agents live and keep them working. You’ll build alongside customer engineering teams, debug production issues, and turn what you learn into product improvements. If you like being in the room when a customer’s agent takes its first real call, and you can trace a dropped call through telephony, webhooks, and the LLM, this role is for you.
You’ll work with Engineering, Product, and Customer Success, and with customer developers, IT teams, and telephony providers.
WHAT YOU’LL DO
Get enterprise customers live and scaling
- Lead technical onboarding for enterprise accounts, from kickoff and architecture review through go-live and ramp.
- Help customers move from pilot to production, including concurrency planning, load readiness, and rollout strategy.
- Build trusted relationships with customer engineering, IT, and security teams.
Build with customers
- Build voice agents with customers in Retell: prompts, conversation flows, knowledge bases, voice and language settings, and call transfer.
- Design integrations with customer systems such as CRMs, scheduling tools, ticketing, and internal APIs, using custom functions, webhooks, and the Retell API and SDKs.
- Advise on conversation design and deployment strategy for new use cases such as inbound support, outbound campaigns, appointment booking, and qualification.
- Work directly in customer codebases when needed.
Debug and resolve production issues
- Troubleshoot live deployments: call quality, latency, interruptions and turn-taking, transcription errors, hallucinations, tool-call failures, and unexpected agent behavior.
- Debug APIs, webhooks, authentication, SIP trunking and telephony (carrier setup, number routing, call transfers, caller ID), and custom LLM integrations.
- Use call logs, transcripts, and post-call analysis to find root causes, then write clear post-incident summaries for…