Member of Technical Staff (Full Time/SFO, CA/Onsite/USA)

Job Title: Member of Technical StaffLocation: San Francisco, CA (Onsite)Job Type: Full Time/PermanentVisa: Full Time/USC/GC/Etc..
The company: a YC-backed AI company automating consumer lending. Over $1 billion in payments processed, ~$6M revenue this year, real-time AI voice running inside top-10 US mortgage lenders. This hire architects and owns the core systems: sub-700ms latency, event-driven architecture, systems that improve with every customer interaction. The archetype is the engineer who walks in, has an opinion on how it should be built, and starts rebuilding it.
Requirements
3+ years professional engineering, strong Python fundamentalsHas personally architected production backends, not just shipped inside someone else's stackDeep understanding of distributed systems, reliability, fault toleranceExcellent database design and performance optimizationKubernetes, event-driven architecture, parallel processingCracked with AI tooling: Claude, Cursor or Codex daily
Background
Distributed systems / low-latency backend at high-bar companies (AWS, Palantir Foundry, Databricks, Snowflake)AI or voice infrastructure (Deepgram, Cartesia, ElevenLabs, Retell, Vapi, Twilio infra)Ex-YC founding engineers with real backend depth
Nice-to-Have
Sub-second latency systems: voice AI, HFT, ad-serving, real-time biddingCompliance-heavy production systems (FDCPA, RESPA, TILA, HIPAA, SOC 2, PCI)Who Will Thrive HereA builder with strong opinions on architecture and the bias to defensibly rebuild what is wrongSomeone who figures things out in messy, high-velocity environmentsSomeone who wants to set engineering culture, not inherit itFully in office, SF, 5 days a week; relocation possible. H-1B transfer and TN are fine, O-1 works, OPT is a hard no.