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Senior Backend Developer

Warszawa, mazowieckie💼 Full-time🗓 2026-02-24 → 2026-08-10

Core

Design and implement backend services and architecture for an AI-driven fitness and wellness product, integrating LLM-powered systems and supporting mobile clients.

Role type

Senior Backend Engineer (AI/ML integration)

Builds

High-load backend services, API integrations for mobile clients, and AI/ML operational pipelines

Domain

Health & Fitness / AI & Machine Learning

Deliverable

production ML models | product features

Required skills

Python (Django/FastAPI), asynchronous systems, relational databases (PostgreSQL), API design, high-load system architecture, operational reliability

Preferred skills

Cloud infrastructure (AWS), Go/Ruby, health/fitness domain knowledge

Technologies

Python, Django, FastAPI, PostgreSQL, AWS, LLMs

Responsibilities

Design and implement backend features supporting core product experiences; Integrate backend with LLM-powered and ML-based systems; Improve performance, scalability, and reliability of existing backend services

Seniority

Senior, hands-on IC

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