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I am a Lead Flutter Developer with over 10 years of experience in software engineering and more than 5 years specializing in building production-ready Flutter applications. I have a proven track record of leading cross-functional teams, conducting technical interviews, and mentoring engineers to build scalable and high-performance applications using Flutter and Node.js. My passion lies in creating user-centric experiences, improving team efficiency, and aligning engineering work with business objectives. I have successfully led the development of CRM systems, educational platforms, and B2C apps used by thousands of users worldwide.…I am a Lead Flutter Developer with over 10 years of experience in software engineering and more than 5 years specializing in building production-ready Flutter applications. I have a proven track record of leading cross-functional teams, conducting technical interviews, and mentoring engineers to build scalable and high-performance applications using Flutter and Node.js. My passion lies in creating user-centric experiences, improving team efficiency, and aligning engineering work with business objectives. I have successfully led the development of CRM systems, educational platforms, and B2C apps used by thousands of users worldwide.

Serhii Buhai

Developer, Programmer, App Developer, +3

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I am a Lead Flutter Developer with over 10 years of experience in software engineering and more than 5 years specializing in building production-ready Flutter applications. I have a proven track record of leading cross-functional teams, conducting technical interviews, and mentoring engineers to build scalable and high-performance applications using Flutter and Node.js. My passion lies in creating user-centric experiences, improving team efficiency, and aligning engineering work with business objectives. I have successfully led the development of CRM systems, educational platforms, and B2C apps used by thousands of users worldwide.…I am a Lead Flutter Developer with over 10 years of experience in software engineering and more than 5 years specializing in building production-ready Flutter applications. I have a proven track record of leading cross-functional teams, conducting technical interviews, and mentoring engineers to build scalable and high-performance applications using Flutter and Node.js. My passion lies in creating user-centric experiences, improving team efficiency, and aligning engineering work with business objectives. I have successfully led the development of CRM systems, educational platforms, and B2C apps used by thousands of users worldwide.

Available to hire

I am a Lead Flutter Developer with over 10 years of experience in software engineering and more than 5 years specializing in building production-ready Flutter applications. I have a proven track record of leading cross-functional teams, conducting technical interviews, and mentoring engineers to build scalable and high-performance applications using Flutter and Node.js.

My passion lies in creating user-centric experiences, improving team efficiency, and aligning engineering work with business objectives. I have successfully led the development of CRM systems, educational platforms, and B2C apps used by thousands of users worldwide.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Language

English

Intermediate

Ukrainian

Fluent

Work Experience

Lead Developer at Let’s Go Solutions

November 1, 2024 - Present

In my part-time role, I architected and developed the “Let’s CV” mobile resume builder app, focusing on simplifying CV creation for non-technical users. I led full development cycles including feature design, publishing, and iterated improvements from user feedback. Currently, I am developing a fitness app emphasizing offline-first data handling, custom training workflows, and cross-device synchronization.

Senior Flutter Developer at Bitmotive, LLC

September 1, 2023 - Present

I modernized the architecture of a music streaming app for improved stability and maintainability while delivering new features centered on user experience and performance. Additionally, I rebuilt an inventory management app to enhance development flexibility and scalability, working closely with product and design teams to ensure alignment with user needs.

Team Lead / Senior Developer at HedgeFun:D

September 30, 2023 - August 9, 2025

Led a team developing a cross-platform educational app with interactive content and parental controls using Flutter and Node.js. Defined architecture, coding standards, and feature roadmaps while designing scalable backend services with Node.js, RabbitMQ, and MongoDB to support multi-language content. Contributed backend functionality to the casino admin panel and real-time gameplay features, participating in code reviews, cross-team collaboration, and technical interviews for backend engineer recruitment.

MEAN Stack Developer at Web-Systems Solutions

September 30, 2019 - August 9, 2025

Developed a real estate CRM system featuring live chat and mobile support, and built a flight booking app with user-friendly UI and optimized checkout flows. Enhanced backend performance using Node.js and Redis while collaborating with design and QA teams for smooth delivery.

MEAN Stack Developer at Upwork

December 1, 2017 - August 9, 2025

Created a delivery service platform with real-time driver tracking and automated route logic. Developed a web platform for sports events organization and a data ingestion system to unify supplier information, emphasizing modular and reusable backend code for long-term scalability.

MEAN Stack Developer at Web-Systems Solutions

February 28, 2017 - August 9, 2025

Built a SaaS-style product management platform for e-commerce businesses and developed interactive HTML5 games for marketing engagement. Implemented responsive, localized user-facing features.

MEAN Stack Developer at WebArtWork

August 31, 2016 - August 9, 2025

Contributed to the development of a freelance job marketplace and participated in an Angular hackathon delivering a prototype under tight deadlines. Collaborated on core features including job posting, search, and user dashboard components.

Lead Developer at Let’s Go Solutions

November 1, 2024 - Present

Led the launch of 'Let’s CV', a mobile resume builder app aimed at non-technical users. Managed all development phases including architecture design, feature implementation, publishing, and user feedback integration. Continuously enhanced the app based on real user testing and usability feedback. Currently developing a mobile-first fitness app focusing on offline-first data, personalized training flows, and cross-device synchronization.

Senior Flutter Developer at Bitmotive, LLC

September 1, 2023 - Present

Modernized the architecture of a music streaming app to enhance stability and maintainability. Delivered new features focusing on user experience and performance. Rebuilt an inventory management app from scratch, improving development flexibility and scalability. Collaborated closely with product and design teams to ensure implementations aligned with user needs.

Team Lead / Senior Developer at HedgeFun:D

September 1, 2023 - August 27, 2025

Led development of a cross-platform educational app for children featuring interactive videos, games, and parental controls using Flutter and Node.js. Managed a development team and defined architecture, code standards, and feature planning. Designed scalable backend services with Node.js, RabbitMQ, and MongoDB supporting multi-language content and media delivery. Contributed as a senior backend developer to casino admin panel features including player management, reporting, payment gateway integration, and real-time gameplay support. Involved in code reviews, architectural discussions, and cross-team collaboration. Conducted technical interviews and onboarded new backend engineers.

MEAN Stack Developer at Web-Systems Solutions

September 1, 2019 - August 27, 2025

Developed a real estate CRM system integrating live chat and mobile support. Built a user-friendly flight booking app with streamlined checkout. Optimized backend performance using Node.js and Redis. Collaborated with design and QA teams for smooth project delivery.

MEAN Stack Developer at Upwork

December 1, 2017 - August 27, 2025

Created a delivery service platform featuring real-time driver tracking and automated routing logic. Developed a web platform for sports event organization. Built a data ingestion system to unify supplier information. Emphasized modular and reusable backend code for scalability.

MEAN Stack Developer at Web-Systems Solutions

February 1, 2017 - August 27, 2025

Developed a SaaS-style product management platform for e-commerce businesses. Created interactive HTML5 games for marketing engagement. Implemented responsive and localized user-facing features.

MEAN Stack Developer at WebArtWork

August 1, 2016 - August 27, 2025

Contributed to the development of a freelance job marketplace. Participated in an Angular hackathon delivering a fully working prototype under time constraints. Collaborated on core features including job posting, search, and dashboards.