Тарас

Taras Haidar
Senior Frontend Developer
Phone: [open contact info](look above in the "contact info" section)
Email: [open contact info](look above in the "contact info" section)
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Summary
Frontend and mobile developer with over 7 years of experience creating web and cross-platform mobile
applications. Expert in React, React Native, TypeScript, JavaScript, and Next.js. Skilled in developing
reusable user interfaces, managing application state, implementing authentication, analytics, localization, and
conducting unit testing. Experienced in mobile release processes and focusing on maintainable solutions, app
performance, and user-friendly interfaces. Utilizes AI-powered tools and automated workflows to speed up
debugging, code reviews, testing, and resolving production issues.

Technical skills
● Programming Languages/Frameworks: React, React Native, TypeScript, JavaScript, Next.js, Node.js,
Expo, HTML, CSS
● UI libraries: Tailwind CSS, Bootstrap 4, Material UI, Semantic UI, Style Components, Base Web
● Frontend libraries: Vite, React Hook Form, React Router, react-i18next, Lodash
● State management: Redux, Redux Toolkit, RTK Query, Redux-Saga
● Product services and APIs: Segment, Google Analytics, Google APIs, Intercom, Lokalise, Sentry,
Stripe, Adapty
● Testing: Jest, Vitest, React Testing Library, Playwright
● Cloud and backend services: AWS Amplify, Amazon Cognito, Firebase
● Build and delivery: Webpack, GitHub Actions, GitLab CI/CD, Vercel, Fastlane
● AI-assisted engineering: Claude, Cursor, GitHub Copilot, CodeRabbit, custom AI agent workflows,
automated test coverage, and AI-assisted Sentry remediation
● Software Development Methodologies: Scrum, Kanban

Education
● Master's Degree in Computer Engineering — Lviv Polytechnic National University,

Languages
● English — B2
● Ukrainian — Native

Experience

September 2022 — Present, Senior Frontend Developer, Timechimp
Project: A dutch SaaS platform for time, cost, and project tracking used by freelancers, SMBs, and enterprise
teams to manage their workforce and billing operations. The application lets users log working hours,
mileage, and expenses, plan and budget projects, and automatically convert tracked time into client invoices.
The platform is built as a multi-device solution (web, desktop, and mobile apps for iOS and Android) with
real-time data sync and integrates with third-party accounting, CRM, and HR systems (e.g. Exact, Yuki,
AFAS, Twinfield, HubSpot, Salesforce) via a public API.

Responsibilities:
● Developing reusable UI components and responsive pages for web and mobile applications of varying
complexity.
● Implementing client-side state management with Redux, Redux Toolkit, and RTK Query.
● Configuring authentication and user access flows with Amazon Cognito.
● Integrating Segment analytics and Google location services to support product analytics and
location-based functionality.
● Implementing application localization and managing translations with Lokalise.
● Reviewing code and refining requirements to support consistent implementation and reliable delivery.
● Preparing and releasing mobile applications to the Apple App Store and Google Play using Fastlane.
● Code maintenance and refactoring.

AI-assisted engineering::
● Using Claude, Cursor in daily development for implementation, debugging, refactoring, code
exploration, and test generation.
● Automating pull request reviews with CodeRabbit to flag potential defects, maintainability concerns,
and code-quality issues earlier in the delivery cycle.
● Designing a custom multi-agent workflow that scans repositories for bugs, reports findings, generates
targeted fixes, and opens pull requests automatically.
● Building an automated test-coverage workflow that identifies coverage gaps, creates relevant tests,
and submits improvements through pull requests.
● Integrating Sentry, AI analysis, and Git context to detect production errors, generate candidate fixes,
and automatically open remediation pull requests.

Achievements:
● Led the launch of the TimeChimp mobile app, successfully releasing it on the App Store and Google
Play.
● Developed and enhanced mobile features such as time tracking, approvals, planning, and real-time
syncing, ensuring a smooth user experience.
● Optimized performance and UI/UX, making time tracking simple and efficient for thousands of users.
● Transitioned focus to the TimeChimp web app, contributing to core product development, new feature
implementations, and long-term scalability.

● Contributed to the migration of the web platform from legacy code to modern React.js, improving
maintainability, scalability, and performance.
● Refactored and modularized code, reducing complexity and increasing development efficiency.

Technologies: TypeScript, React, React Native, Next.js, Redux, Redux Toolkit, RTK Query, Amazon
Cognito, Segment, Google APIs, Lokalise, Fastlane

October 2020 — September 2022, Frontend Developer, Oril
Project: A mental health and wellbeing mobile app for iOS and Android. It helps users manage stress by
consolidating biometric data from wearables (Apple Watch, Garmin) into an overall stress score across sleep,
cardiac activity, and movement. The app also includes the "Odyssey" framework — a guided assessment of
personality, emotional intelligence, and burnout risk — alongside a bi-weekly Perceived Stress Assessment
(PSS), combining objective biometric and self-reported stress data.

Responsibilities:
● Developing reusable React and React Native UI components and application screens.
● Integrating Firebase services for in-app notifications.
● Writing unit tests with Jest for implemented functionality.
● Integrating Adapty to support mobile payment functionality.
● Reviewing code to maintain consistency and implementation quality.
● Preparing and releasing mobile applications to the Apple App Store and Google Play using Fastlane.
● Code maintenance and refactoring.

Achievements:
● Developed the mobile app from scratch, implementing core features such as biometric data tracking,
stress monitoring, and personalized stress management tools.
● Integrated smartwatch data (Apple Watch & Garmin), enabling real-time stress level analysis based on
sleep, cardiac activity, and physical movement.
● Built an interactive "Odyssey" framework, guiding users through personalized insights on stress,
burnout, and emotional intelligence.
● Implemented a flexible subscription model, allowing users to access premium features while
maintaining a free-tier experience.
● Optimized performance and UI/UX, ensuring smooth interactions and fast data synchronization.

Technologies: TypeScript, React, React Native, Redux, Redux-Saga, Jest, Firebase, Adapty, Fastlane

June 2019 — October 2020, Frontend Developer, Incora
Project: Development of an online food ordering and delivery platform for a fast-food restaurant chain. The
system replaces phone-based ordering with a digital channel where customers browse menus, customize
orders, and choose between pickup or tracked delivery. The platform supports four distinct user roles —
admins, supervisors, customers, and guests — with admins managing menu items, discount coupons, delivery
time limits, and supervisor permissions.

Responsibilities:

● Developing reusable UI components and pages with React and TypeScript
● Setting up the frontend project and its Webpack-based build configuration from scratch
● Implementing client-side state management with Redux and Redux-Saga
● Integrating Google APIs to support platform functionality
● Reviewing code and contributing to requirement refinement and delivery planning
● Code maintenance and refactoring.

Achievements:
● Developed a robust admin dashboard using React.js, enabling managers to track orders, update menus,
and analyze sales in real time.
● Optimized performance, reducing dashboard load times and ensuring smooth data updates for
high-traffic usage.
● Implemented role-based access control, enhancing security by restricting sensitive data to authorized
users.
● Integrated real-time order tracking, allowing restaurant staff to monitor and fulfill orders seamlessly.
● Collaborated with designers and back-end developers to create an intuitive and responsive UI,
ensuring a seamless experience across devices.

Technologies: TypeScript, React, Redux, Redux-Saga, SCSS, Webpack, Lodash, Google APIs