Andrey Osiyuk

• Built a lightweight GraphQL client for SmartTV and console React apps across 6+ platforms (Tizen 2015+, WebOS 2014+, Orsay 2012+, Vidaa, PlayStation 4/5) serving 2.7M+ daily users — Apollo and similar clients were too heavy for low-memory, slow-CPU TV hardware, so wrote a custom client with build-time query pre-compilation to cut runtime overhead and a REST-like API so teams could adopt it without rewriting their code
• Architected the frontend data layer migration for cross-platform React apps (2.7M+ daily users, 6+ platforms) — designed and delivered a BFF layer so 4 product teams (~11 engineers) could move from REST to GraphQL across 130+ endpoints without performance regressions, wrote migration docs, and coordinated the rollout with backend and infrastructure teams
• Built custom GraphQL codegen with Webpack and esbuild plugins to simplify frontend data fetching, integrated OpenTelemetry tracing for cross-service debugging, and load-tested the BFF to validate capacity for peak traffic (New Year), determining horizontal scaling needs for 4,000+ RPS
• Designed the frontend i18n architecture for cross-platform React apps (~1,000 translation keys, 4 languages including RTL Arabic) — set up runtime language switching with on-demand dictionary loading, precompiled ICU format to keep bundles small, wired up key sync with the internal translation service, and added CI checks for missing translations. This enabled the product launch into MENA and Uzbekistan (~200K new daily users)
• Wrote a custom vanilla-extract plugin for RTL stylesheet generation and a React context service for dynamic LTR/RTL DOM switching, which unblocked the Arabic-language launch. Also introduced React Testing Library and built a Puppeteer-based request mocking plugin for Testplane — removed the dependency on backend staging and made e2e tests significantly more stable
• Cut CI/CD pipeline time from 30+ to ~15 minutes for a 400K+ line TypeScript monorepo (6 teams, 18 engineers) by leading the Webpack 4→5 migration, improving caching in custom build plugins, and restructuring the CI pipeline

Developed enterprise web applications for clients including VTB Bank and Beeline using React, Redux, MobX, and TypeScript

Built web applications using React and TypeScript, including a music beat marketplace with GraphQL backend integration and a crypto wallet marketing site