Senior Backend Engineer, Gateway

Role overview A senior backend role owning large portions of a high-throughput gateway that authenticates requests, enforces budgets and policy, routes traffic to multiple provider connections, and records latency, token usage, and estimated costs. The stack is TypeScript on Cloudflare Workers with Postgres behind it, and the work emphasizes correctness under concurrency, performance on the hot path, and honest measurement.

Responsibilities - Design and ship gateway features end to end, covering request handling, provider adapters, streaming responses, and the error taxonomy customers build against. - Add support for new provider kinds and wire formats without introducing special cases in the router. - Keep the hot path lean by avoiding per-request tokenization, unbounded queries, and slow downstream waits. - Write schema migrations and tests against real Postgres, including the concurrency cases unit tests cannot cover. - Participate in an on-call rotation and author runbook entries for anything shipped.

Requirements - Five or more years building production backend services, including at least one system that handled real traffic and real billing data. - Strong TypeScript fluency and comfort inspecting HTTP, SSE, and JSON wire formats at the byte level. - Solid Postgres skills across schema design, migrations, indexing, transactions, and query plan analysis. - Experience designing for idempotency, retries, and race conditions in distributed systems. - Clear written communication, since most decisions are made in writing.

Nice to have - Production experience with Cloudflare Workers, Durable Objects, KV, or Queues. - Hands-on integration work with LLM provider APIs such as OpenAI, Anthropic, Bedrock, Vertex, or Azure OpenAI. - Familiarity with Hono, Drizzle, or other edge-first TypeScript stacks.