Sergii B. — Full Stack Developer

Expertise in Full Stack Web, User Interface and Experience Designer (UI/UX).

Last verified on May, 2026

Core Skills

Bio Summary

Full-Stack Developer with 3 years of experience specializing in Python (FastAPI, Flask), Java (Spring Boot with Hibernate), and modern JavaScript frameworks (React, Next.js), delivering scalable web applications and microservices.
Proficient in API integrations, real-time communication (WebSockets, SSE), and cloud-native development using Docker, AWS, and CI/CD pipelines with GitHub Actions.
Hands-on expertise in RDBMS (PostgreSQL, MySQL), NoSQL (MongoDB, Redis), and advanced front-end state management (Redux, Redux-Saga, RTK Query) with UI/UX optimization and performance tuning.

Technical Skills

Programming Languages	Java, JavaScript, Python
JavaScript Frameworks	Ext JS, React
Python Frameworks	FastAPI, Flask
JavaScript Libraries and Tools	i18next, Leaflet, Mobx, React Router, Redux-Saga, Redux Thunk, Redux-toolkit, RTK-query
AI & Machine Learning	NumPy, OpenAI, PandasAI
Python Libraries and Tools	NumPy, Pydantic
Java Frameworks	Spring Boot
Security	Auth0
Data Analysis and Visualization Technologies	MapBox, PandasAI
Databases & Management Systems / ORM	MongoDB, MySQL, Redis, SQLAlchemy
UI Frameworks, Libraries, and Browsers	Bootstrap 4, Chart.js, Material UI, Socket.io, Tailwind CSS
Cloud Platforms, Services & Computing	AWS
Methodologies, Paradigms and Patterns	Agile, FDD, Kanban, OOP, Scrum, Waterfall
Deployment, CI/CD & Administration	Axios, GitLab CI
Message/Queue/Task Brokers	Celery
SDK / API and Integrations	FastAPI, Google Maps API, Python Requests Library, Stripe
Version Control	Git, Github Actions
QA, Test Automation, Security	Jest, Mock, React Testing Library
Third Party Tools / IDEs / SDK / Services	Microsoft Visual Studio Code, PyCharm
Logging and Monitoring	Sentry
Mail / Network Protocols / Data transfer	WebSockets
Other Technical Skills	Framer-motion, SSE

Work Experience

Full Stack Developer (European information page (Webia and Infocheck))

Duration: 2 years
Summary:

Webia and Infocheck are information pages where users can find comprehensive information about European companies or their managers
The platform contains about 15 million pages, serving as a large-scale web development project focused on data accessibility and user experience

Responsibilities:

Back-end development
Front-end development
UI/UX improvements
Implementing new features
API integrations
Lead management
SEO optimization
Performance optimization and monitoring
Development, build and deployment scripts
Improving system architecture
Code base refactoring
Fix bugs
Unit testing
Code review

Technologies: Python, FastAPI, Next.js, TypeScript, Redux-Saga, Axios, Chart.js, Auth0, Websockets, PostgreSQL, Docker

Full Stack Developer (RAG system for info classification)

Duration: 1 year
Summary:

The RAG system project involved classifying user-provided information according to documented rules within the sales domain
The system aimed to automate and improve the accuracy of information classification to support sales processes

Responsibilities:

Back-End Development
Front-End development
Improved UI/UX design
Software architecture design
Implementing new features
API integrations
Development and maintenance of API documentation
Unit testing
Fix bugs
Code review

Technologies: Python, FastAPI, React, TypeScript, Redux, Axios, RTK Query, Material UI, Chart.js, SSE, PostgreSQL, Docker

Education

Master's degree Odessa State Academy of Civil Engineering and Architecture
Civil, industrial engineering and construction

Certification

Front End Basic (HTML/CSS)
Hillel IT school, Odesa
Front End Pro (JavaScript, React)
Hillel IT school, Odesa
AWS Certified Cloud Practitioner
AWS Java Pro
Hillel IT school, Odesa
Java Enterprise
Hillel IT school, Odesa

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