Senior Backend Engineer (FastAPI)

Quick Facts

• Leads backend that powers AI features
• Focus: APIs, data pipelines, orchestration, retrieval, tool-calling, streaming, and reliable async workloads

Description

You will lead the backend that drives the AI features—APIs, data pipelines, and orchestration connecting the product to language models.

The work includes querying across large document sets, producing trustworthy LLM answers (including tool calls), streaming results to the UI, and running lengthy background jobs reliably. The main challenge is making AI systems fast and reliable on confidential data at production scale.

Responsibilities

• Architect and ship APIs and services everything else depends on
• Own AI plumbing end to end: retrieval, orchestration, tool-calling, streaming, and evals to verify result quality
• Build solid async and distributed workloads for ingestion, embeddings, and long-running jobs (e.g., using Redis)
• Integrate with client tools (email, document stores) and harden integrations for real-world traffic
• Put data security and isolation first to prevent leakage of confidential material

Requirements

• 7+ years delivering production backends (depth matters more than the exact figure)
• Think in failure modes, not only happy paths
• Shipped LLM systems (RAG, tool-calling, agents) or eager to do so
• Experience with async/distributed workloads
• Data security and isolation experience
• Python 6+ years
• FastAPI 3+ years
• PostgreSQL/SQL
• Redis 2+ years

Benefits

The role emphasizes owning architecture decisions early and living with them in production, using AI coding tools (Claude Code, Cursor, Copilot) with careful code review discipline, and working in a fast-changing startup environment where plans get set then revised.