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YAROSLAV
KHMARSKYI
FULL-STACK WEB DEVELOPER
Email: [відкрити контакти](див. вище в блоці «контактна інформація»)
Telegram | linkedin

WHY ME WORK HISTORY
Full-Stack Web Developer focused on React/Nest.js, AWS,
and AI-integrated products, with 4.5 years of experience Full Stack Developer
shipping end-to-end features across frontend, backend, Feb. 2025 – Jul. 2026
and infrastructure. Strongest work spans web3, crypto, and CRYPTO CASINO SERVICEs (FaucetPay & Pasino)
AI platforms with ownership of product-facing systems.
Migrated two production casino sites from a legacy frontend
architecture to a modern one, with a new design, faster load times,
HIGHLIGHTED SKILLS and smaller bundle sizes
Languages - Javascript, Typescript, Python Contributed to technical decisions as part of a 10-person team,
proposing and discussing architecture and implementation
Back-end - Node.js, Nest.js, Express.js, Fastify approaches
Made backend adjustments as needed to support frontend changes
Front-end - React.js, Next.js, Vue.js, HTML5/CSS3 and new requirements
Onboarded two new developers and took part in code reviews to help
State Management - Redux Toolkit, Zustand, RxJS maintain quality across the team

Data Visualization - PixiJS, React Flow, Chart.js, D3.js ANTIFRAUD SYSTEM
Built an automated bot detection system for casino and betting sites,
AWS - S3, EC2, AMI, Cloud Watch, Load Balancer, replacing a manual review process with real-time classification of
CloudFront, Auto Scaling Groups suspicious sessions and accounts
Implemented behavioral analysis (mouse movement, click patterns,
Databases - MySQL, PostgreSQL, Redis, MongoDB session timing) and device fingerprinting to distinguish bots from real
users
ORM: TypeORM, Prisma, Drizzle Designed and built an API and web interface for reviewing flagged
activity, with search and filtering across multiple parameters plus
API & Integration - REST API, WebSocket, GraphQL, RPC metrics and sorting
Owned the architecture and technology decisions across the stack
CI/CD - Docker, GitHub Actions
INFRASTRUCTURE ORCHESTRATION WITH NOMAD
Other - GIT, Bitbucket, Jira, Asana Introduced HashiCorp Nomad to orchestrate services across 8 servers,
replacing manual service management
Basic knowledge - PHP, Solidity, FunC, Rust Set up and configured the Nomad cluster to automate deployment and
scheduling of services
AI Integration - LLM integration, prompt engineering, and Improved operational efficiency and reliability as the infrastructure
intelligent workflow development grew

PREVIOUS EDUCATION Full Stack Developer
Jul. 2024 – Feb. 2025
National University "Zaporizhzhia Polytechnic"
Crypto TG GAME (MemHustle)
MASTER OF ENGINEERING | 2015 - 2020
Contributed to a Telegram-based tower defense game built with
Electric drive and automation of industrial plants PixiJS with crypto rewards for players, owning the payment system,
animations, and bug fixes
Built the payment system handling in-game crypto transactions
LANGUAGES Implemented new animations and sound effects and improved existing
English - Intermediate ones to enhance gameplay
Ukrainian - Native Fixed bugs across game logic and mechanics to improve stability
WORK HISTORY

ADMIN PANEL FOR MEMHUSTLE
Built an admin panel giving the team visibility into player payments, in-game progress, and account state
Implemented payment tracking with full transaction history and statuses, making it possible to investigate failed or stuck crypto payments
Added player overview with progress, balance, and account status, plus search and filtering to quickly find a specific user

Full Stack Developer
Jan. 2022 – Jul. 2024
AI-POWERED CONTENT GENERATION PLATFORM (AUTOFUNNEL)
Worked in a team on an AI platform that turns a user's text prompt into a customizable website — and later books — as the product scaled
Implemented block-level customization, letting users edit any section manually or by re-prompting AI to regenerate it
Integrated ChatGPT for text generation and Midjourney/DALL-E for images
Built an admin panel with analytics (visit and view statistics) and subscription management
Automated deployment on AWS using GitHub Actions for seamless releases and updates
AI-POWERED GREETING CARD GENERATOR
Built a full-stack AI greeting card generator solo — React frontend, Nest.js backend
Integrated OpenAI for text and Midjourney/DALL-E for image generation
Implemented user management and payment processing

AI PERSONA CHAT WIDGET
Built an embeddable iframe chat widget (frontend + backend) that clients drop into their site, letting visitors ask questions and get answers in
the client's own voice
Integrated an LLM trained on the client's talks to reproduce their speaking style
Configured TLS certificates with Let's Encrypt / Certbot

NFT MARKETPLACE & WEB3 GAME PLATFORM (MECH.COM)
Built an NFT marketplace from scratch on Ethereum, letting the client sell NFTs directly and avoid third-party platform fees (e.g. OpenSea)
Implemented wallet integration (MetaMask) 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