Senior FastAPI Developer

Newcode; United States; Remote; USD 140,000 - 200,000; Full time

Benefits offered by this job

Remote role

English-speaking team

Job summary

Newcode is seeking a senior backend engineer to design and operate the backend systems powering AI features for professional services. You will own APIs, data processing, model orchestration, and reliable delivery for confidential documents, including streaming responses and long-running background jobs.

You will work in a small, fast-moving team with ownership of system design, and collaborate on secure, scalable architecture while adapting to evolving priorities and technologies.

Qualifications

• At least seven years building production backend systems.
• Six+ years of Python experience and three+ years with FastAPI.
• At least two years working with PostgreSQL or SQL and Redis.
• Practical understanding of failure modes in backend services and AI-powered systems.
• Familiarity with LLM applications such as retrieval-augmented generation, tool-calling, or agents.
• Comfort adapting as priorities and technical decisions change.

Responsibilities

• Design and maintain APIs and backend services for product features.
• Build retrieval, model orchestration, tool-calling, response streaming, and evaluation workflows.
• Make document ingestion, embedding generation, and long-running Redis-backed jobs reliable.
• Integrate with client systems such as email and document stores, and support them under load.
• Protect confidential data through careful security and tenant isolation practices.
• Use AI coding assistants responsibly, reviewing and understanding generated code before it ships.

Skills

Backend systems

Python

FastAPI

PostgreSQL/Redis

LLM apps

Security & isolation

Failure modes

Tools

PostgreSQL

Redis

Job description

Role overview

Build and operate the backend systems that power AI features used in professional services. The work spans APIs, data processing, model orchestration, and dependable delivery of results from confidential documents, including streamed responses and long-running background jobs. You’ll have meaningful ownership of system design in a small, fast-moving team.

Responsibilities

• Design and maintain APIs and backend services for product features.
• Build retrieval, model orchestration, tool-calling, response streaming, and evaluation workflows.
• Make document ingestion, embedding generation, and long-running Redis-backed jobs reliable.
• Integrate with client systems such as email and document stores, and support them under load.
• Protect confidential data through careful security and tenant isolation practices.
• Use AI coding assistants responsibly, reviewing and understanding generated code before it ships.

Requirements

• At least seven years building production backend systems.
• Six or more years of Python experience and three or more years with FastAPI.
• At least two years working with PostgreSQL or SQL and Redis.
• Practical understanding of failure modes in backend services and AI-powered systems.
• Familiarity with LLM applications such as retrieval-augmented generation, tool-calling, or agents, or a strong readiness to work in these areas.
• Comfort adapting as priorities and technical decisions change.

Nice to have

• Experience with retrieval or vector search, LangChain, or LlamaIndex.
• Streaming experience with SSE, WebSocket, or SignalR.
• Microsoft Graph or email integration experience.

Benefits and work setup

• Remote role for candidates authorized to work in their applicable country. Visa sponsorship is unavailable.
• English-speaking team and scope to help shape the product and team as they grow.