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Full-Stack Developer
Full-Stack Developer with 4.5 years of experience building end-to-
end web products, from architecture and database design to
backend, frontend, and infrastructure. Specialized in React, Nest.js,
TypeScript, and blockchain integrations. Built two production
crypto casino platforms, an NFT marketplace, and a real-time
antifraud system.

Work experience
Newtone (Jan. 2022 - Jul. 2026)
Crypto casino services (FaucetPay & Pasino)
Led the migration of two production casino platforms from a
legacy frontend architecture to a modern React-based
solution, improving maintainability, reducing bundle size, and
significantly enhancing page load performance.
Collaborated with a cross-functional team of 10 engineers on
architectural decisions, feature design, and implementation
Yaroslav Khmarskyi strategies.
Implemented full-stack features, making backend changes
Email: [відкрити контакти](див. вище в блоці «контактна інформація»)
in Nest.js to support new frontend functionality and evolving
Telegram | Linkedin
business requirements.
Languages
Antifraud system
English Intermediate +
Designed and developed an automated bot detection
Ukrainian Native
system for casino and betting platforms, replacing manual
review with real-time session and account risk assessment.
Technical Skills Implemented behavioral analysis (mouse movement, click
Programming Languages patterns, session timing) together with device fingerprinting
TypeScript to identify automated activity and distinguish bots from
JavaScript (ES202x) legitimate users.
Python Built REST APIs and an internal web dashboard for
Back-end investigating flagged users, featuring advanced search,
filtering, sorting, and operational metrics.
Node.js
Designed the system architecture, database schema, and
Nest.js
Express.js
technology stack, taking ownership of technical decisions
Fastify throughout the project.

Frontend Server Administration
React Introduced HashiCorp Nomad to orchestrate services across
Vue.js 8 servers, replacing manual service management
HTML5 Administered VPS servers, including initial setup, health
CSS / SCSS / JSS monitoring, application uptime maintenance, and
State Managemen deployment of new versions.
Configured and deployed monitoring infrastructure using
Redux Toolkit
Zustand Prometheus and Grafana to track server health and
RxJS application metrics.

ORM Blockchain Integrations
TypeORM Implemented microservices using NestJS for cryptocurrency
Prisma operations, including deposit detection and withdrawal
Drizzle processing for assets such as SOL, TON, ADA, and others
Modernized legacy microservices by improving fault
Databases
tolerance, implementing fallback mechanisms, and reducing
MySQL
blockchain RPC request volume by more than 50%
PostgreSQL
Designed and implemented a staking microservices
Redis
MongoDB
supporting Taraxa, BSC, and TON blockchain integrations.

API & Integration Crypto tg game (MemHustle)
REST API Developed core features for a Telegram-based tower
WebSocket defense game built with React and PixiJS, including
GraphQL gameplay improvements and crypto reward integration.
RPC
Designed and implemented the in-game payment system
Data Visualization for processing cryptocurrency transactions.
PixiJS Created and enhanced gameplay animations and sound
React Flow effects to improve the overall player experience.
Chart.js
Admin panel for MemHustle
D3.js
Designed and developed an internal admin panel for
CI/CD managing players, monitoring game activity, and
Docker investigating cryptocurrency payments.
GitHub Actions
Implemented payment tracking with transaction history,
AWS statuses, and failure diagnostics, simplifying investigation of
S3 failed or pending payments.
EC2 Built player management features, including account
AMI overview, game progress, balances, and advanced search
Cloud Watch and filtering.
Load Balancer
Ai-powered content generation platform
CloudFront
Auto Scaling Groups
(Autofunnel)
Worked in a team on an AI platform that turns a user ' s text
Testing tools
prompt into a customizable website — and later books — as
Jest
the product scaled
Vitest
Implemented block-level customization, letting users edit
Playwright
any section manually or by re-prompting AI to regenerate it
AI Integration Integrated ChatGPT for text generation and
LLM integration Midjourney/DALL-E for images
Prompt engineering Built an admin panel with analytics (visit and view statistics)
Intelligent workflow development and subscription management
Automated deployment on AWS using GitHub Actions for
Basic knowledge
seamless releases and updates
PHP
Solidity Ai persona chat widget
FunC Built an embeddable iframe chat widget (frontend +
Rust backend) that clients drop into their site, letting visitors ask
Other questions and get answers in the client' s own voice
GIT Integrated an LLM trained on the client' s talks to reproduce
Bitbucket their speaking style
Jira Configured TLS certificates with Let' s Encrypt / Certbot
Asana Nft marketplace & web3 game platform
(MECH.COM)
Education
Built an NFT marketplace from scratch on Ethereum, letting
National University "Zaporizhzhia Polytechnic "
the client sell NFTs directly and avoid third-party platform
Master of engineering
fees (e.g. OpenSea)
2015 - 2020
Implemented wallets integration and interaction with
Ethereum smart contracts using Ethers.js, handling
transactions and user balances
Developed the marketplace ' s full UI from the provided
design, owning the entire frontend
Contributed to the companion browser-based Godot game:
built the in-game currency bundle purchase flow and HTML-
side animations (e.g. loading screen) driven by Godot' s
output