Open to opportunities

Wiktor Jin

@wiktorjin

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Senior Full Stack Engineer with 8+ years of experience.

Poland

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What I'm looking for

I'm looking for a challenging role in a dynamic company that values innovation and teamwork, offering opportunities for growth and development.

I'm a Senior Full Stack Engineer based in Warsaw with over 8 years of experience in building scalable web applications. My expertise lies in Python, Django, FastAPI, and modern JavaScript frameworks like React and Next.js. I have successfully led projects that include financial analytics platforms and geospatial dashboards, demonstrating my ability to deliver high-quality solutions in agile environments.

Throughout my career, I've developed and maintained robust backend APIs, optimized database queries, and implemented serverless architectures on AWS. My commitment to clean code and team mentorship has been instrumental in driving project success and fostering a collaborative work environment. I thrive on challenges and continuously seek opportunities to enhance my skills and contribute to innovative projects.

Experience

Work history, roles, and key accomplishments

Senior Software Engineer

Netguru

Apr 2024 - Present (1 year 4 months)

Developed and maintained scalable backend APIs in Python using Django and FastAPI for a real-time financial analytics platform, handling ~250K daily trades and margin calculations. Designed PostgreSQL schemas and optimized complex reporting queries, reducing data fetch times for daily and historical dashboards by 40%.

Python Django fastAPI PostgreSQL AWS Lambda S3 Celery Redis React Next.js GitHub Actions)Docker Prometheus Grafana ELK

Senior Software Engineer

Mapped

Feb 2023 - Present (2 years 6 months)

Engineered TypeScript/Express microservices to unify location metadata from 5 internal APIs, boosting data accuracy in location search by 25%. Led front-end development using React/Next.js for a live geospatial dashboard, integrating Mapbox GL and Chart.js to display multi-layer heatmaps updated in real time.

TypeScript React Next.js Mapbox Chart.Js SQS Lambda Redis DynamoDB Prometheus Grafana Docker Helm EKS Cypress

Full Stack Engineer

Andela

Apr 2021 - Present (4 years 4 months)

Designed and implemented backend systems in Python/Django REST Framework to manage user profile matching, team invites, and messaging workflows, scaling to support the placement of 10,000+ engineers. Developed a profile-scoring engine using a weighted algorithm, improving candidate-to-project match accuracy by 35%.

Python Django REST Framework Flask PostgreSQL Redis Pytest FactoryBoy Gitlab CI Agile Factory Boy

Frontend Web Developer

Asseco Poland

Sep 2019 - Present (5 years 11 months)

Developed enterprise-grade web apps for banking and insurance dashboards using React/Next.js, emphasizing secure design, cross-browser compatibility, and performance optimization. Architected a reusable component library styled with Tailwind CSS, accelerating frontend development across three major client projects.

React Next.js Tailwind Axios .NET Java Jira GitHub Actions)Agile

Back End Developer

MakoLab

Jul 2017 - Present (8 years 1 month)

Built Node.js/Express REST services and PostgreSQL databases to power product catalogs, shopping carts, and checkout systems for high-traffic e-commerce platforms. Created real-time data sync pipelines linking MySQL, Elasticsearch, and Redis using Python and Bash scripts, enabling sub-second search and filtering for users.