Senior/Staff Backend Engineer, Backend Platform

Remote (US) Close ( https://close.com ) | Senior/Staff Backend Engineer, Backend Platform | Full-time
We're bootstrapped, profitable, and 130 people, all remote, building an AI-powered CRM. We're spinning up a new Backend Platforms team and you'd be one of the first hires — unusual influence over what it owns.
You'd build for other engineers: the paved-road patterns under our Python/Flask API layer (REST + GraphQL, auth, permissions, migrations), the Flask→FastAPI path, production observability standards, and our AI dev platform — DevDawg (cloud dev environments for the whole stack) and Spice (our agent layer that already auto-approves simple PRs). Making Spice safe across more of our review surface is the team's biggest project.
Stack: Python, Flask, FastAPI, GraphQL, TaskTiger, Rust, TypeScript, Kafka, Redis, MongoDB, PostgreSQL, Elasticsearch, Docker, Kubernetes, AWS.
Looking for: deep Python, shipped LLM/agentic work to real users, daily coding-agent use with a real POV, strong observability and API design instincts.
Also: ~5 weeks PTO + winter break, optional 4-day week at 80% pay, 1-month sabbatical every 5 years, 99% of medical premiums covered, 401k match to 6%.
Our code: https://github.com/closeio (TaskTiger, SocketShark, ciso8601)
Eng blog: https://making.close.com
Apply: https://jobs.ashbyhq.com/close/5bf4629b-d2ee-4129-980f-e31b9...