Денис

Denis Yakovlev
Senior Front-End Developer
[open contact info](look above in the "contact info" section) | [open contact info](look above in the "contact info" section)
[open contact info](look above in the "contact info" section) | Telegram: @dadya_denis

PROFESSIONAL SUMMARY
Senior Front-End Developer with 7 years of experience building scalable web applications and complex user interfaces, including 5
years with React and 4 years with TypeScript. Skilled in designing application architecture, leading refactoring initiatives, and
improving performance across large-scale enterprise systems as well as products built from scratch.
Experienced in Team Lead responsibilities: conducting code reviews, maintaining technical standards, coordinating sprint planning,
and mentoring junior and middle developers. Comfortable working directly with cross-functional teams and stakeholders to translate
business requirements into effective technical solutions.
Leverages AI-assisted development tools (Claude Code, Gemini) to accelerate feature delivery while maintaining code quality -
configures project-level context (CLAUDE.md) and integrates MCP servers (Figma, browser DevTools) to streamline
design-to-code handoff and automate debugging and network/console error analysis.
KEY EXPERIENCE SNAPSHOT
Total professional experience: 7 years
React: 5 years
TypeScript: 4 years
TECHNICAL SKILLS
Languages: JavaScript, TypeScript
Frontend Frameworks: React, Next.js, Vue, Angular
State Management & Data Fetching: Redux, RTK Query, TanStack Query
Backend: Node.js, NestJS, TypeORM, REST API, WebSocket
Testing: Jest
Styling & UI Libraries: Sass, SCSS, Tailwind CSS, Styled Components, Material UI, Ant Design, Ark UI
Cloud & Platform Tools: AWS, Firebase, Google Maps API, Google Tag Manager (GTM)
PROFESSIONAL EXPERIENCE

Senior Front-End Developer / Team Lead - VeliTechJan 2024 – Apr 2026
Large-scale sportsbook platform ecosystem: customer-facing applications, administration tools, and supporting backend services with
extensive integrations across multiple external providers. Team of 24 (5 front-end). Stack: React, Redux, RTK Query, TanStack Query,
TypeScript, Jest, Angular, Node.js, NestJS, WebSocket, Styled Components.
Leadership & Team Contribution
• Led large-scale code reviews and helped establish front-end development standards, improving consistency and code quality
across the team.
• Authored and maintained technical documentation and style guides used team-wide.
• Owned sprint planning, backlog grooming, and team syncs for a cross-functional team of 24 members.
• Mentored junior and middle developers on a regular basis, helping them improve code quality, architectural understanding, and
development practices.
Sportsbook Platform (React, TypeScript, RTK Query, WebSocket)
• Developed and maintained sportsbook functionality with complex business logic, translating business requirements into
production-ready features.
• Implemented new features and integrations with external data and betting providers.
• Led refactoring initiatives that improved maintainability and consistency across the front-end codebase.
• Audited front-end API requests for real-time odds data and compiled a list of 10 payload optimization proposals for the
backend team, including consolidating 3 duplicated template-based requests into a single parameterized endpoint; 7 of the 10
proposals were accepted for implementation.
Administration Panel (Angular)
• Developed and maintained administrative functionality used for platform configuration and management.
Launcher Service (NestJS, TypeORM)

• Implemented backend functionality responsible for platform initialization, template selection, state validation, and request
routing.
Internal Tooling
• Built a Chrome extension that automated support workflows, reducing repetitive manual operations for the support team.
Platform-Wide Initiatives
• Identified scalability limits in the front-end-only i18n setup when a third language was introduced, and proposed migrating
translation management to the admin panel with per-partner, per-language storage; the proposal was accepted and implemented,
reducing the front-end bundle size by removing statically bundled translation files in favor of runtime-fetched content.
Middle Front-End Developer - Django StarsAug 2022 – Oct 2023
Large-scale survey platform for insurance companies enabling dynamic form creation, custom branding, and offline data collection.
Customer: a US company. Team size: 7. Stack: React, RTK Query, TypeScript, Jest, Mustache, Google Maps API, AWS, Firebase.
• Implemented offline-first functionality using Service Workers, IndexedDB, Firebase, and local synchronization mechanisms,
enabling reliable data collection without a network connection.
• Delivered new product features and enhanced existing components across a highly configurable survey platform.
• Implemented new UI designs and improved user workflows across multiple application modules.
• Maintained and expanded automated test coverage to ensure product stability and reliability.
• Investigated and resolved application defects, supporting ongoing product development.
• Took full ownership of the front-end application as the sole front-end developer on the project - responsible for feature delivery,
maintenance, technical decisions, and stakeholder demos.
Junior Front-End Developer - InoXoftJul 2021 – Jul 2022
Customer: a US company. Stack: React, Redux, RTK Query, TypeScript, Next.js.
PWA for Media Creation & Cloud Storage (4 months, team of 8)
• Developed features for a Progressive Web Application focused on media creation (photo, video, audio) and cloud storage
management.
• Built reusable React components and application modules for media-related workflows.
• Collaborated with designers and back-end developers to deliver new functionality.
Real Estate SPA - Florida Housing Marketplace (8 months, team of 10)
• Owned end-to-end delivery of several product features, from requirements clarification to implementation and release.
• Developed key business modules including account management, property pages, community functionality, and house-selling
workflows.
• Built reusable React components and maintained consistency across shared UI patterns.
• Introduced the project's first Bitbucket Pipeline configuration, establishing an automated deployment process.
Senior HTML/CSS Developer - RubyGarageDec 2019 – Jul 2021
Stack: React, Redux, React Native, JavaScript, HTML5, CSS3, SCSS.
• Developed pixel-perfect user interfaces based on design specifications and product requirements.
• Built reusable React components and shared UI modules to improve consistency and accelerate feature development.
• Collaborated with designers, QA engineers, and developers in cross-functional teams of up to 20 members.
• Implemented responsive, cross-browser-compatible layouts across web and mobile applications.
• Contributed front-end implementation feedback that informed ongoing UI/UX improvements.
EARLIER EXPERIENCE
Junior Front-End Developer - KultprosvetMar 2019 – Oct 2019
Vue.js / Vuex / GSAP - built a document-management platform (create, edit, share PDFs with custom fields) and redesigned the UI for the
KIVI TV store. Team of 4, Israeli client.
Front-End Developer - Sugar.Soft.DesignMar 2018 – Mar 2019
JavaScript / jQuery / WordPress / GSAP - sole developer covering front-end, animations, and client communication for local business
websites.

EDUCATION
Oles Honchar Dnipro National University
Specialist Diploma, Control Systems for Aircraft and Systems - Faculty of Physics and Technology [add graduation year]
SPOKEN LANGUAGES
English: Upper-Intermediate
Ukrainian: Native
Russian: Native