Web3 Engineer / Senior Backend & Blockchain Engineer
Mstsislaw, Mahilyowskya, Belarus
Web3 Engineer with 5+ years of experience in blockchain development, smart contract engineering, and decentralized systems. Proficient in building scalable dApps on Solana Anchor and Ethereum (Solidity). Experienced in tokenomics, wallet integrations (Phantom, Metamask), NFT deployment, gas optimization, and security. Passionate about next-gen Web3 and decentralized gaming.
Salary
USD 86,000 – 140,000
Laba Labs
Mar 2026 — Present
Led full redesign of backend architecture including payments, security, and transaction processing. Implemented fault-tolerant cryptocurrency and fiat payment systems with TON integration, idempotency, reentrancy protection, and escrow logic. Built webhook processing, internal Telegram notification system, PostgreSQL optimization, Grafana/Prometheus observability stack, and managed Ubuntu-based infrastructure with Docker and Nginx.
X11.im
Aug 2025 — Mar 2026
Designed custodial and non-custodial wallet solutions using Java and Metamask. Deployed meta-transaction infrastructure on Polygon for gasless onboarding. Integrated cross-chain bridges, built ERC-1155 marketplaces, engineered staking and epoch-based reward contracts, and extended NFT contracts with RWA tokenization and on-chain governance.
InstaXchange
Apr 2025 — Jun 2025
Developed core backend services in Python with RESTful APIs for authentication, authorization, and dashboard logic. Implemented database sharding, automated failover mechanisms, secure session management, and infrastructure hardening.
Performance Lab
Apr 2024 — Apr 2025
Developed backend logic for banking applications using Java and Node.js. Designed CI/CD pipelines with GitLab CI, worked with PostgreSQL and MySQL, monitored production services with Prometheus and Slack alerts.
NDA
Jan 2024 — Oct 2024
Built responsive frontend UI for Telegram mini-app, integrated WebSocket and TON Connect/WalletConnect. Developed backend in Rust and C++, implemented cryptographic functions, RESTful APIs, smart contract integrations on Solana and TON, and conducted load testing with JMeter.
Performance Lab
Sept 2023 — Jan 2024
Built backend processes using Java and Cucumber-JVM. Developed financial business logic, ensured database consistency across PostgreSQL and MySQL, conducted performance testing, and performed code reviews.
Skillwill - The Science of Productivity
Dec 2022 — Aug 2023
Developed and maintained RESTful APIs using Swagger, Postman, and SOAP UI. Worked with Oracle, PostgreSQL, MongoDB, Kafka, ClickHouse, Hadoop, and Apache Ignite. Automated API testing and configured CI/CD pipelines. Supported React-based frontend integration.
Yandex
Apr 2021 — Dec 2021
Participated in development and support of internal services for data analysis and project management. Built backend logic and frontend components, integrated internal APIs and databases, conducted code reviews, and optimized inter-service communication.
FLEXBOYS studio
May 2020 — Aug 2024
Built and deployed smart contracts on Solana (Rust/Anchor) and Ethereum (Solidity) for DeFi, NFT marketplaces, and gaming. Designed tokenomics including staking, yield farming, and governance. Integrated Phantom and Metamask wallets, developed cross-chain bridges with LayerZero and Wormhole, and contributed to React-based dApp frontends.
Bachelor's · Economics/Banking
2015 – 2019