Open to opportunities

Denis Maryanskiy

@denismaryanskiy

Message

I’m a backend engineer shipping production async Python services with FastAPI, PostgreSQL, and Redis (EU-remote).

Hungary

Message

What I'm looking for

I’m looking for an EU-remote-friendly backend role building production async Python services (FastAPI/PostgreSQL/Redis) with strong testing, CI/CD, and Docker—part-time up to 30h/week or B2B contract.

I’m an EU-remote backend engineer with 4+ years shipping production Python services, specializing in async FastAPI, PostgreSQL, and Redis. I now freelance as a sole developer on full async FastAPI products—each delivered with 95%+ test coverage, CI/CD, and Docker.

Earlier, at Yandex, I led international market expansion (+1.5× driver registrations, 4 new markets) and re-architected a legacy monolith into microservices. Later, I was promoted to Team Lead at Quasar, where I grew the engineering team from 6 to 10 and took ownership of key system design and delivery outcomes.

I build with a strong engineering ethos: clean access control, reliable automation (reports, pipelines, schedulers), and measurable quality improvements. From Quasar’s CI/CD acceleration (40% faster deployment, 60% less review time) to my current async Telegram Mini Apps and Bots, I focus on shipping production-ready systems that stay maintainable.

Experience

Work history, roles, and key accomplishments

Current

Freelance Backend Engineer

Current

Maxpro

Feb 2026 - Present (5 months)

Built an async FastAPI + PostgreSQL platform for operator scheduling, service catalog, client records, and shift reporting. Implemented scoped multi-role JWT auth, automated PDF/Excel reporting, and CI/CD Docker-based deployments with 98%+ test coverage.

Python fastAPI PostgreSQL Alembic JWT Pytest Docker CI CD Ruff Mypy Pre Commit Docker Compose React TypeScript Ant Design React Query Zustand Axios Vitest

Current

Freelance Backend Engineer

Current

Leet Beauty

Jun 2025 - Present (1 year 1 month)

Developing async backend for a beauty e-commerce Telegram Mini App and manager Telegram bot. Built REST APIs with FastAPI + PostgreSQL + asyncpg, Redis cart with atomic Lua scripts, order lifecycle with bot notifications and APScheduler reminders, and Prometheus/Grafana monitoring.

Python fastAPI PostgreSQL Asyncpg Redis Lua JWT Python Telegram Bot Prometheus Grafana Docker React TypeScript Ant Design

Team Lead / Backend Engineer

Quasar

Feb 2025 - Jan 2026 (11 months)

Led backend development for an engineering documentation management system, owning team projects after promotion to Team Lead. Designed role-based access controls, implemented file watermarking and download registry, set up CI/CD with automated testing and static analysis, and refactored a C++/Python system into microservices.

Python Go Alembic SQLAlchemy PostgreSQL gRPC Redis Docker CI CD Microservices Access Control Watermarking Static Analysis

Software Engineer

Yandex.Taxi

May 2023 - Dec 2024 (1 year 7 months)

Worked on ride-hailing driver registration systems across Eastern Europe and MENA, expanding into multiple new markets and employment types. Helped refactor a legacy monolith into microservices to improve maintainability and reduce errors/time to fix by 40%.

Python Userver Framework Prometheus Grafana Clickhouse Kubernetes Microservices

Intern Python Developer

Sber

Apr 2022 - Oct 2022 (6 months)

Developed anonymization software to replace personally identifiable information (PII) in documents with synthetic values. Built analyzers and replacement modules, prototyped an improved anonymization pipeline, and added comprehensive backend test coverage.

Python Flask AllenNLP SQLAlchemy Pytest Anonymization PII (Synthetic Replacement)NLP

Education

Degrees, certifications, and relevant coursework

Eötvös Loránd University

Master of Science (MSc) in Computer Science (AI), Artificial Intelligence

2026 - 2028

Pursuing an MSc in Computer Science with a focus on AI at Eötvös Loránd University (expected Sep 2026–Aug 2028). Relocating to Budapest for the program.