Sergey Alekseev
About
Results-driven Frontend Developer with 3+ years of experience building scalable, high-performance React/TypeScript applications. Specialized in SSR with Next.js, test automation, and clean architectural patterns like Feature-Sliced Design. Strong focus on developer experience, performance optimization, and maintainability. See projects at github.com/serord.
Experience
Frontend Developer
ITCustoms
Aug 2023 – Nov 2024
- Delivered 3+ CRM systems for B2B clients, improving business process efficiency across sectors.
- Reduced redundant HTTP requests by 70% via smart caching strategies and memoized data fetches.
- Refactoredlegacy apps into modular Feature-Sliced Design, cutting bug rates by 50%.
- Introduced Effector for scalable state architecture with clear domain separation and testability.
- Maintained 80%+ test coverage using Vitest, RTL, and Cypress.
- Configured CI/CD with Coolify + GitHub Actions for zero-downtime deploys and branch previews.
Frontend Developer
GrowBank (Crypto Fintech MVP)
Jun 2022 – Aug 2023
- Built and launched crypto banking dashboard used by 1K+ users from the ground up using React and Next.js.
- Improved TTI by 80% and reduced CLS by 95% with SSR, skeletons, and hydration fixes.
- Optimized bundle by 40% using @next/bundle-analyzer and dynamic imports.
- Set up automated deployment to Vercel with test and lint gating via GitHub Actions.
Freelance Frontend Developer
Multiple Clients
Aug 2021 – Jul 2022
- Created landing pages, catalogs, and SPAs for education, e-commerce, and food delivery use cases.
- Built food delivery MVP with geolocation-based filters and modular state management (Effector + React Query).
- Implemented CI with GitHub + Coolify; ensured test coverage with Cypress + RTL.