AI-Driven Backend Engineer (Python/FastAPI)

Greenstep; Vantaa; Hybrid; EUR 65,000 - 90,000; Full time

Benefits offered by this job

Flex benefits

Lunch discount

Together bonus (10% profit share)

Greenstep Academy training

Well-being program

Job summary

Greenstep is hiring a Backend Engineer in Finland to design and implement AI-enabled backend services. You will ship REST APIs in Python/FastAPI and build agent workflows with LangChain/LangGraph, collaborating with data and frontend teams.

Hybrid work culture with a strong emphasis on quality, testing, and observability. You will work closely with the product owner to drive scalability and AI/MCP roadmap, influencing architecture and delivering robust, production-grade software that connects

Qualifications

• 3+ years professional Python backend development, including async programming.
• OOP and clean service architecture.
• REST API design (FastAPI).
• ORMs & migrations (SQLAlchemy, Alembic).
• Practical AI agent building — LangChain/LangGraph.
• Testing discipline: unit/integration/API tests, mocking LLM calls.
• Docker (containerization — no orchestration ownership).
• Basic CI familiarity.
• Excellent English, Finnish is preferred.

Responsibilities

• Design and develop backend services and REST APIs in Python/FastAPI, including agentic workflows built with LangChain and LangGraph.
• Build and expose tools/agents via MCP (FastMCP).
• Build features and APIs on top of consolidated semantic-model and gold-layer data — turning data into product, not just serving it up raw.
• Design database schemas and migrations (SQLAlchemy & Alembic).
• Write asynchronous, production-grade Python, with solid test coverage including mocking LLM/agent calls.
• Containerize services with Docker for local dev and deployment — you won't own Kubernetes or infra, but your services need to ship clean.
• Instrument agent behavior with real observability, so non-deterministic failures are debuggable, not mysterious.
• Use AI coding tools to move faster, with engineering judgment intact.

Skills

3+ years Python backend

Async programming

OOP & clean architecture

REST API design (FastAPI)

Testing (unit/integration)

CI/CD familiarity

English proficiency

Finnish preferred

Tools

Docker

SQLAlchemy

Alembic

LangChain

LangGraph

FastAPI

Job description

Greenstep is hiring a Backend Engineer in Finland to design and implement AI-enabled backend services. You will ship REST APIs in Python/FastAPI and build agent workflows with LangChain/LangGraph, collaborating with data and frontend teams.

Hybrid work culture with a strong emphasis on quality, testing, and observability. You will work closely with the product owner to drive scalability and AI/MCP roadmap, influencing architecture and delivering robust, production-grade software that connects