I am an experienced Flutter developer with over 7 years of experience and a diverse project background. I am also a devoted team lead, guiding small Flutter teams for over 2 years. My focus in application development has been primarily on iOS and Android platforms, utilizing the Flutter framework. Apart from client side application design and logic, I have a lot of experience mentoring small teams of Flutter developers, making sure their code quality is in line with the best industry practices and helping them find the most plausible solution if they get stuck on a problem or need any advice. In some cases, I have also participated in estimating the complexity of individual tasks and even entire projects. In my LinkedIn profile, you can find more information about my previous work experience, as well as some side projects I have been working on in my free time. Check it out: _Website not available. Sign in: https://www.twine.net/signup_ I am passionate about developing impactful products, and if you have one, I hope I will be a good fit for your team.

Kostiantyn Rybalka

I am an experienced Flutter developer with over 7 years of experience and a diverse project background. I am also a devoted team lead, guiding small Flutter teams for over 2 years. My focus in application development has been primarily on iOS and Android platforms, utilizing the Flutter framework. Apart from client side application design and logic, I have a lot of experience mentoring small teams of Flutter developers, making sure their code quality is in line with the best industry practices and helping them find the most plausible solution if they get stuck on a problem or need any advice. In some cases, I have also participated in estimating the complexity of individual tasks and even entire projects. In my LinkedIn profile, you can find more information about my previous work experience, as well as some side projects I have been working on in my free time. Check it out: _Website not available. Sign in: https://www.twine.net/signup_ I am passionate about developing impactful products, and if you have one, I hope I will be a good fit for your team.

Available to hire

I am an experienced Flutter developer with over 7 years of experience and a diverse project background. I am also a devoted team lead, guiding small Flutter teams for over 2 years.

My focus in application development has been primarily on iOS and Android platforms, utilizing the Flutter framework. Apart from client side application design and logic, I have a lot of experience mentoring small teams of Flutter developers, making sure their code quality is in line with the best industry practices and helping them find the most plausible solution if they get stuck on a problem or need any advice. In some cases, I have also participated in estimating the complexity of individual tasks and even entire projects.

In my LinkedIn profile, you can find more information about my previous work experience, as well as some side projects I have been working on in my free time. Check it out: Website not available. Sign in: https://www.twine.net/signup

I am passionate about developing impactful products, and if you have one, I hope I will be a good fit for your team.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate

Language

English
Fluent
Ukrainian
Fluent
Russian
Fluent
Spanish; Castilian
Beginner

Work Experience

Senior Flutter Developer & Team Lead at Rise Apps
July 1, 2023 - Present
Led a small Flutter development team to build a remote monitoring and AI-driven run-tracking application. Responsibilities included training plan structure implementation, run-tracking adjustments, multi-location security monitoring concepts, complex entity-type filters, and custom sign-in functionality. Ensured code quality aligned with industry standards, mentored teammates, and estimated and distributed work across developers.
Senior Flutter Developer at HeyTech, Inc.
February 1, 2021 - Present
Developed the Heylol app (social messenger with video carousel and gamification). Implemented core modules (auth, chat, media, explore, profile, wallet), and coached junior/mid-level developers. Used Dart/Flutter for client-side and Firebase Cloud Functions (Node.js) for server logic; Cloud Firestore for data storage. Built for Android and iOS, implemented in-app purchases and native/ad integrations, and performed unit, widget, and integration testing. Localized app for English and Russian; implemented advanced routing with goRouter. Applied thorough documentation, multi-platform readiness, and robust routing, state restoration, and external sharing support.
Flutter Developer at Data Root Labs
March 1, 2018 - Present
Contributed to Flutter-based applications across finance, entertainment, education, and catering sectors. Managed full application lifecycle from research and development to testing and deployment. Primarily utilized Flutter with occasional Kotlin/Swift for native components, and participated in architecture decisions and testing strategies.
Middle / Senior Flutter Developer at HeyTech, Inc.
February 1, 2021 - Present
Developed the Heylol app as a senior Flutter developer for a social messenger with video carousel and gamification elements; implemented major system modules: auth, chat, media, explore, profile, wallet, tasks, gifts. Mentored junior and mid-level developers; used Dart/Flutter for client-side and Firebase Cloud Functions with Node.js for server-side logic; utilized Cloud Firestore for data storage; developed for Android and iOS; conducted unit, widget and integration testing; implemented modular authentication for reusability; app documentation and localization for English and Russian.
Junior / Machine Learning Engineer at Data Root Labs
March 1, 2018 - Present
While at Data Root Labs I participated in complex and innovative ML/AI projects. Responsibilities included data collection for training, designing model architectures, fine-tuning parameters, and training and deployment of models.

Education

Bachelor's degree in Computer Science at Taras Shevchenko National University of Kyiv
September 20, 2017 - April 6, 2026
Bachelor's Degree in Computer Science at Taras Shevchenko National University of Kyiv
January 11, 2030 - September 20, 2017

Qualifications

Add your qualifications or awards here.

Industry Experience

Software & Internet, Media & Entertainment, Education, Financial Services, Travel & Hospitality

Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate

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