Backend / AI Developer - Freelancer at Monterail

Monterail; Warszawa; On-site; PLN 165,000 - 331,000; Full time

Job summary

Monterail is seeking a Backend/AI Developer (Freelancer) for an on-site role in Warszawa, Poland. You will join an enterprise project building an AI Transformation platform that automates back-office processes and provides AI-driven decision support.

You will work on data integration, agent development, MCP servers, and a robust backend architecture to connect data, agents, and front-end apps. The position emphasizes Python, FastAPI, Docker, PostgreSQL, and experience with LLMs.

Qualifications

• Solid commercial experience in backend development with Python.

Responsibilities

• Integrate data from multiple sources into a cohesive data layer.
• Build and deploy AI agents for business tasks (signal analysis, pricing, data tagging).
• Develop MCP servers exposing data to agents and tools.
• Do data engineering: schema design, ETL, data synchronization and quality control.
• Contribute to agent platform architecture: routing, cost control, access policies, telemetry for LLM calls.
• Design and build backend APIs connecting data layer with agents and front-end apps.
• Create user-facing tools driven by data and agent insights.
• Maintain infrastructure: containerization, databases, monitoring, observability.
• Document architectural decisions and maintain contracts between system layers.

Job description

Apply for Backend / AI Developer - Freelancer at Monterail in Warszawa, MZ, PL.

This Full time on site position offers great opportunities for career growth.

About the Project

We're building an AI Transformation platform for an enterprise client, focused on back-office process automation and AI-driven decision support. The platform brings together data from multiple business systems and puts AI agents on top of it, so that business teams get actionable insights and automated workflows instead of manual routines.

Requirements What You’ll Do

• Integrate data from multiple business sources (CRM, analytics, BI) into a single, cohesive data layer
• Build and deploy AI agents that execute specific business tasks: signal analysis, pricing, content/SEO, data classification and tagging
• Develop MCP (Model Context Protocol) servers: dedicated, read-only, domain-specific servers that expose data to agents and tools
• Do data engineering work: schema design, ETL and synchronization from external systems, and ensuring data quality and consistency
• Contribute to the agent platform architecture: routing layer, cost control, access policies, and telemetry for LLM calls
• Design and build backend APIs connecting the data layer with agents and front-end applications
• Create user-facing tools for business teams, driven by data and agent-generated insights
• Maintain infrastructure: containerization, database management, monitoring, and observability
• Document architectural decisions
• and keep strict contracts between system layers

Tech Stack Python · FastAPI · Agno (agent framework) · MCP · PostgreSQL · Docker / Docker Compose · Next.js

What we are looking for:

• Solid commercial experience (approx. 2 years) in backend development with Python
• Hands‑on experience with FastAPI or a comparable modern web framework
• Good knowledge of PostgreSQL: schema design, query writing, and optimization
• Experience building and consuming REST APIs
• Understanding of ETL and data synchronization concepts, and of how to keep data consistent across systems
• Working knowledge of Docker and Docker Compose
• Practical experience with LLMs and prompt writing; interest in building agent-based systems
• Comfort working with agentic AI tools (e.g., Claude Code) in daily development, and the discipline to critically verify their output
• Ability to write clear technical documentation
• Good communication skills and confidence working directly with client‑side teams
• English level sufficient for daily communication with the client (B2+ / Upper-Intermediate)

Nice to Have

• Experience with agent frameworks (Agno, LangChain, LlamaIndex, or similar)
• Familiarity with MCP (Model Context Protocol)
• Basic Next.js / React skills for working on front-end applications
• Experience with observability and monitoring tools
• Experience integrating with CRM, analytics, or BI systems
• Background in enterprise or consulting projects

What do we mean by freelance?

Read more at Monterail Tech Network*