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Kostiantyn H.

@holovanych7

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5.0
1
2.0
2.0
100%

✅Mobile&Web✅Game development✅Python✅OpenAI✅AI/ML

$30 USD / Hour
Flag of
Ukraine (7:22 PM)
Joined on December 4, 2024
$30 USD / Hour
✔ Delivering High-Performance Cross-Platform and Web Applications With over 4 years of hands-on experience with React Native, Next.js, Node.js, Three.js and Machine Learning, I specialize in building robust, user-friendly mobile and web applications that meet user needs, focusing on performance, scalability and innovative design. ✔ Core Expertise: ✅ Mobile App Development - React Native for seamless iOS and Android apps. ✅ Web Development - Next.js for lightning-fast, SEO-friendly web applications. ✅ Backend Development - Node.js for building efficient, scalable and fast backend solutions. ✅ 3D Visualization - Three.js for immersive 3D web experiences. ✅ AI Integration - implementing machine learning for intelligent data analysis and user interaction. ✔ Special Skills: End-to-end mobile and web application development. Optimize app and website performance for rapid responsiveness. Implement advanced state management (Redux, MobX, Context API). Integrate third-party APIs and build custom solutions. Create pixel-perfect UI/UX designs based on Figma/Sketch concepts. Advanced user authentication, payment gateway integration, and security. ✔ Why work with me I believe that every idea deserves technical excellence and a thoughtful approach. I focus on developing scalable solutions tailored to your unique goals using creativity, technical expertise, and professionalism. Whether you are building a product for a startup, scaling an existing app, or experimenting with innovative technology solutions, I am here to bring your vision to life. ✔ Proven Success: ✅ Reduced app load time by 30% through optimization strategies. ✅ Provides customized solutions for industries such as e-commerce, healthcare, finance, AI/ML, and social media. ✔ Let's improve your vision! Are you ready to build a next-generation app or integrate innovative technologies into your business? Whether it's mobile, web, or machine learning-based projects, I'm ready to help you turn your idea into reality. ✔ Send me a message today! Let's collaborate and bring your vision to life.
Verifications
On time
100%
On budget
100%
Accept rate
100%

Portfolio

Portfolio

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5.0 · 1 Review
Reviews
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Kostiantyn exceeded my expectations on my React Native project. :) He demonstrated a strong understanding of the framework and delivered high-quality results promptly. His communication was excellent; he kept me updated throughout the process and was always open to feedback. Kostiantyn's attention to detail and problem-solving skills made the collaboration smooth and enjoyable. I highly recommend him for any development work and would gladly work with him again!
Runze J.
@runzej7
Flag of
上海, China
2 months ago
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Experience
Senior Full Stack Developer
May, 2024 - Nov, 2024
5 months, 30 days
ELEKS
May, 2024 - Nov, 2024
5 months, 30 days
Delivered high-quality web applications through robust full-stack development practices. Mentored junior team members, fostering a collaborative and efficient development environment. Enhanced cloud infrastructure by optimizing APIs hosted on Azure Kubernetes Services (AKS). Resolved performance bottlenecks, ensuring smooth application performance.
Flag of
remote, Ukraine
May, 2024 - Nov, 2024
5 months, 30 days
Principal Software Engineer
Nov, 2023 - Apr, 2024
5 months
SoftServe
Nov, 2023 - Apr, 2024
5 months
Spearheaded the design and development of advanced features for enterprise-level applications. Conducted unit testing with Jest and integrated end-to-end testing with Cypress, achieving 80%+ code coverage. Implemented Git-based CI/CD pipelines, streamlining the testing and deployment processes. Enhanced UI/UX design based on Figma mockups for client-facing portals. Developed and maintained 200+ reusable components with Storybook, improving cross-team efficiency.
Flag of
remote, Ukraine
Nov, 2023 - Apr, 2024
5 months
Education
State University 'Lviv Polytechnics'
2019 - 2023
4 years
bachelor of computer science
Flag of
Ukraine
2019 - 2023
4 years
Qualifications
React Native certification
2020
HackerRank
Received React Native Certification
2020
React certification
2020
HackerRank
Received React certification at HackerRank
2020
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