AI-Powered Backend Engineer

Monterail; Kraków; On-site; PLN 100,000 - 167,000; Part time

Job summary

Monterail is seeking a backend developer to join an AI Transformation project in Kraków. The role emphasizes building and deploying AI agents, data integration, and MCP servers for a data-driven platform used by enterprise teams.

You will work on data engineering, API design, and system observability, collaborating with client-side teams and contributing to the overall architecture. This freelance opportunity requires strong Python skills, experience with FastAPI, and familiarity with

Qualifications

• 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).

Responsibilities

• 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 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.

Skills

Python

FastAPI

PostgreSQL

REST APIs

ETL

Docker

LLMs

Agno

LangChain

Next.js

Observability

CRM/BI integration

Tools

Docker Compose

PostgreSQL tooling

API design tools

Job description

Monterail is seeking a backend developer to join an AI Transformation project in Kraków. The role emphasizes building and deploying AI agents, data integration, and MCP servers for a data-driven platform used by enterprise teams.

You will work on data engineering, API design, and system observability, collaborating with client-side teams and contributing to the overall architecture. This freelance opportunity requires strong Python skills, experience with FastAPI, and familiarity with