AI Software Engineer (Python & React)

Technologies we use

Expected

• React.js
• TypeScript
• Python
• OpenAI API
• FastAPI
• LangChain
• Microsoft Azure

Your responsibilities

• Design, develop and maintain full-stack applications using React, TypeScript and Python.
• Build and integrate LLM-powered applications using the OpenAI API, including RAG pipelines, prompt engineering and structured outputs.
• Implement vector and hybrid search solutions and document parsing for PDF, Word and Excel files.
• Evaluate and monitor LLM applications using tools such as Langfuse or similar platforms.
• Develop and integrate backend services using FastAPI or equivalent frameworks.
• Work with Microsoft Azure services, including virtual machines, application hosting and Entra ID/SSO.
• Translate business requirements into technical specifications, provide clear status updates and manage changing or ambiguous requirements.

Our requirements

• Strong hands-on experience with React, TypeScript and Python.
• Experience delivering at least one LLM-powered application to production.
• Practical knowledge of RAG, prompt design, structured outputs and the OpenAI API.
• Experience with vector or hybrid search and document parsing.
• Familiarity with LLM evaluation and observability tools, such as Langfuse.
• Working knowledge of Microsoft Azure, including VMs, application hosting and Entra ID/SSO.
• Excellent client-facing and communication skills.
• Fluency in spoken and written English.
• Must overlap as closely as possible with US working hours

Optional

• Experience developing MCP servers or integrating Claude and AI agents.
• Knowledge of PII protection and GDPR requirements, including Microsoft Presidio and EU data residency.
• Experience in finance, private equity or M&A due diligence.

Benefits

• sharing the costs of sports activities
• private medical care
• remote work opportunities

SQUARE ONE RESOURCES sp. z o.o.

#OneSquareOne - one team, many talents

Square One Poland specializes in IT outsourcing and supporting companies in building and scaling technology teams. We help international organizations access proven IT specialists, carefully matched to project requirements and company culture.

We act as a strategic partner, enabling effective team scaling — from individual experts to complete project teams — based on transparent cooperation and long-term, win–win relationships. For IT professionals, we offer inspiring projects delivered with modern technologies, clear communication, and real opportunities for professional growth.

Operating internationally, we combine years of experience with creativity, agility, and flexibility. Despite our market maturity, we retain a start-up DNA that allows us to respond quickly to changing business needs.

Our organizational culture is confirmed by the Great Place to Work® 2026 certification.

This is how we work