Location: Seattle, WA
Remote: Yes
Willing to relocate: Yes (SF, NYC for the right team)
Technologies: Go, Python, Rust, TypeScript, Kotlin | LLM agents, multi-agent orchestration, MCP, RAG | Postgres, Redis, Kafka, gRPC, Kubernetes | AWS, GCP, Cloudflare | Cadence/Temporal, Playwright/CDP
Résumé: https://elninja.com/resume
LinkedIn: https://www.linkedin.com/in/elninja
GitHub: https://github.com/ibarrajo
Email: alex [at] elninja.com
I build agent systems. A decade in production distributed systems (Uber, DoorDash, Jobscan); the last year spent designing and shipping autonomous, LLM-driven infrastructure. Looking for a hands-on senior IC role on an AI-infra / agent-platform / applied-AI team.
Background: at Uber, worked on Cadence (open-source workflow engine, 12B+ workflows/month internally) — executed multi-region failovers on domains doing billions of ops/day, shipped non-determinism detection via shadow replay, rebuilt cadenceworkflow.io, onboarded 50+ teams. At DoorDash, refund rules engine for McDonald's/Chipotle (500K refunds/month). At Jobscan, Senior Software Engineer: 97% → 99.99% uptime through an AWS migration, $475K/yr recovered via payment A/B testing. I've operated durable-execution systems at scale and have opinions about where that paradigm earns its keep and where autonomous agents are the better tool — which is what I build now.
ibarrajo · · focus · HN ↗
Background: at Uber, worked on Cadence (open-source workflow engine, 12B+ workflows/month internally) — executed multi-region failovers on domains doing billions of ops/day, shipped non-determinism detection via shadow replay, rebuilt cadenceworkflow.io, onboarded 50+ teams. At DoorDash, refund rules engine for McDonald's/Chipotle (500K refunds/month). At Jobscan, Senior Software Engineer: 97% → 99.99% uptime through an AWS migration, $475K/yr recovered via payment A/B testing. I've operated durable-execution systems at scale and have opinions about where that paradigm earns its keep and where autonomous agents are the better tool — which is what I build now.