Backend / AI Developer - Freelancer at Monterail

Monterail; Województwo pomorskie; On-site; PLN 120,000 - 180,000; Full time

Job summary

Monterail is looking for a backend developer to join our on-site team in Gdańsk. You will build and scale an AI transformation platform, focusing on data integration, backend services, and agent-driven workflows.

The role emphasizes robust data engineering, API design, and system observability within a modern Python stack. You will work with FastAPI, PostgreSQL, and Docker, contributing to MCP servers and agent frameworks while communicating effectively with client teams.

Qualifications

• 2+ years of commercial backend Python experience.
• Proficient with FastAPI or a comparable modern framework.
• Strong PostgreSQL skills: schema design, queries, optimization.
• Experience building and consuming REST APIs.
• Hands-on Docker/Docker Compose usage.
• Practical exposure to LLMs and agent-based systems.
• Excellent written and spoken English (B2+).

Responsibilities

• Integrate data from multiple sources into a cohesive backend data layer.
• Build and deploy AI agents that perform specific business tasks.
• Develop MCP servers to expose data to agents and tools.
• Design data schemas, ETL processes, and ensure data quality.
• Contribute to the agent platform architecture and routing logic.
• Create backend APIs connecting data with front-end applications.
• Document architecture decisions and enforce clear contracts between layers.
• Maintain infrastructure: containerization, databases, monitoring, observability.

Skills

Python

FastAPI

PostgreSQL

REST APIs

Docker

LLMs

Agent-based systems

English B2+

Job description

This Full time on site position offers great opportunities for career growth. Gdańsk, PM, PL

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 systemsWorking 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?