Senior FastAPI Engineer

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About our clientWe’re hiring for a growing technology company developing AI software for legal and professional services organizations. Its products help teams navigate large volumes of documents, find relevant information, and handle knowledge-intensive work involving sensitive data.

The company already serves paying customers and is expanding its engineering team to support further product development.

About the roleAs a Senior Python / FastAPI Developer, you’ll be responsible for the backend services that turn AI capabilities into dependable product features.

You’ll connect language models with application logic and data sources, build document processing workflows, and ensure that background tasks and user-facing APIs operate reliably as usage grows. The role combines hands-on development with architectural ownership, with particular attention to performance, data protection, and the quality of AI-generated results.

Your responsibilities

• Develop and maintain APIs and backend services in Python and Fast
• API
• Build workflows for document retrieval, LLM orchestration, tool execution, and response streaming
• Implement evaluation mechanisms to measure and improve AI output quality
• Design asynchronous pipelines for document ingestion, embedding generation, and time-consuming processing tasks
• Build and maintain integrations with email services and document management platforms
• Address performance bottlenecks and failure scenarios across distributed services
• Ensure secure handling of confidential information and clear separation of customer data
• Contribute to architecture decisions and engineering standardsRequirements7+ years of experience developing backend systems used in productionAt least 6 years of Python experience and 3 years working with Fast
• API
• Practical knowledge of PostgreSQL and SQLAt least 2 years of experience with RedisA strong understanding of asynchronous processing, system reliability, and designing for failure
• Experience with LLM-based systems, or a strong motivation to work with RAG, agents, and tool-calling
• Effective use of AI development tools such as Claude Code, Cursor, or Copilot, with full responsibility for code qualityA proactive approach to technical ownership and comfort with changing startup priorities
• Tech stack
• Backend: Python, Fast
• API
• Database: PostgreSQL / SQL
• Caching & background processing: Redis, Celery
• Messaging: Rabbit
• MQCloud: Microsoft AzureNice to have
• Experience building RAG solutions or implementing vector search
• Familiarity with LangChain or Llama
• Index
• Knowledge of SSE, WebSocket, or Signal
• RExperience integrating Microsoft Graph or email platforms
• What you can expect
• Direct influence on backend architecture and product development
• Close collaboration with a small engineering team
• Practical AI challenges involving real customers and production workloadsA flexible, English-speaking environment
• The opportunity to help shape engineering practices as the team expands