Full Stack Developer & React Native Engineer
Over 6 years of experience building web and mobile applications. Specialized in React Native mobile development with a strong foundation in full-stack development.
Experience
Here's a brief rundown of my work history, key responsibilities, and notable achievements at each company.
Senior Frontend Developer
StellarUp/Morrison Street Advisors • Remote
Industrial IoT / Monitoring
2025 May - Present
Contract
- Built a multi-tenant industrial monitoring platform with Next.js, delivering real-time alerts, dashboards, and data-management workflows with secure role-based access
- Designed and shipped a Next.js app with App Router, server actions, and typed APIs covering alerts, components, facilities, data metrics, and uploads
- Implemented invitations and role-based access; enforced tenant isolation and organization-level workflows
- Delivered interactive dashboards and data management via reusable UI components and feature-oriented architecture
- Enabled PWA capabilities (manifest, service worker) and web push notifications; added i18n with message validation and locale routing
- Provisioned AWS infrastructure with CDK; integrated CI/CD via Bitbucket Pipelines and containerized builds
- Improved reliability with Jest and consistent linting/formatting; documented APIs and developer workflows
Senior Frontend Developer
StellarUp • Budapest, Hungary
Social Media, Marketing
2023 September - 2025 May
Contract
- Built a mobile application prototype for a social media and lifestyle platform with a connected webstore
- Developed the mobile app, webstore, and website featuring post sharing, live feeds, live support chat, and e-commerce capabilities
- Contributed to the web platform development using Next.js, creating seamless integration between mobile and web interfaces
- Building a social platform that facilitates connections between influencers and brands for marketing collaborations
- Implementing best practices and architectural decisions for both mobile and web applications
Full Stack Mobile Developer
Gridlock Inc. • Remote
Crypto wallet
January 2023 - February 2024
Contract
- Led planning and development of data backup feature using Google Drive, iCloud, Keychain, and encryption techniques
- Implemented in-app purchases and subscriptions for Play Store and App Store
- Designed and developed offline capabilities for the application
- Optimized site performance, improved animations, and enhanced UI responsiveness
- Maintained high coding standards and conducted code reviews
- Managed deployment processes for both Play Store and App Store
Full Stack Software Developer
Viddl • Budapest, Hungary
Package delivery, E-learning
May 2021 - January 2023
Full-time/Contract
- Maintained and enhanced web and mobile applications
- Contributed to complete mobile frontend codebase rewrite for improved scalability
- Developed multiple E-learning platforms, including HSUP, used by thousands of students
- Created package delivery tracking application with map view using OpenLayers and VROOM
- Refactored data structure to improve package status visualization
Full Stack Web Developer
Asseco Central Europe Zrt. • Budapest, Hungary
Healthcare
September 2018 - May 2021
Full-time
- Contributed to the development of an Information Sharing Platform for Hungarian healthcare organizations
- Developed a conference platform with audio-video calls using WebRTC technology
Services
Specialized development services tailored to your needs, focusing on modern web and mobile solutions.
Web Development
Building modern, responsive web applications with cutting-edge technologies.
- •Custom web application development
- •Progressive Web Apps (PWA)
- •Frontend and backend integration
- •Performance optimization
- •SEO-friendly development
Mobile Development
Creating cross-platform mobile applications for iOS and Android.
- •React Native development
- •Cross-platform solutions
- •Store deployment
- •Development take over and maintenance
Technical Consulting
Providing expert guidance on technology solutions and architecture decisions.
- •Architecture planning
- •Technology stack selection
- •Code review and optimization
- •Performance auditing
- •Technical documentation
Let's Create Something Amazing
Have an idea? Whether you're a startup with a vision or an established company looking to innovate, I'm here to help turn your ideas into reality. Here's how we can work together:
Understanding Your Vision
Let's start by exploring your ideas and goals together. I'll help you shape and refine your vision into a concrete plan.
What We'll Do
- •In-depth consultation
- •Goal exploration
- •Technical possibilities
- •Strategic planning
What You'll Get
- •Detailed project vision
- •Technical roadmap
- •Timeline & milestones
- •Resource outline
Crafting the Blueprint
Together, we'll design a solution that's not just functional, but scalable and future-proof for your growing needs.
What We'll Do
- •Collaborative design sessions
- •Technology selection
- •User experience planning
- •Security & scaling strategy
What You'll Get
- •System blueprint
- •Technology stack
- •Interactive prototypes
- •Security framework
Bringing Ideas to Life
Watch your vision become reality through iterative development. Regular updates keep you involved every step of the way.
What We'll Do
- •Iterative development
- •Continuous collaboration
- •Quality assurance
- •Progress reviews
What You'll Get
- •Working software
- •Quality reports
- •Documented code
- •Progress insights
Launch & Growth
Your success is my priority. I'll ensure a smooth launch and provide ongoing support to help your solution thrive.
What We'll Do
- •Strategic deployment
- •Performance optimization
- •Knowledge transfer
- •Growth support
What You'll Get
- •Production release
- •Training resources
- •Maintenance plan
- •Growth roadmap
Ready to Start Your Project?
Whether you have a specific project in mind or just want to explore possibilities, I'm here to help. Let's discuss your ideas and find the best way to bring them to life.
Let's Talk About Your ProjectProjects
A selection of my recent development projects and technical achievements.
Industrial Monitoring Platform (Multi-tenant)
May 2025 - Present
Multi-tenant industrial monitoring platform with real-time alerts, dashboards, and secure role-based workflows built with Next.js.
Social Media and Lifestlye Platform
Sep 2024 - Present
A social platform connecting influencers with brands for marketing collaborations, featuring both a React Native mobile app and a Next.js web application.
Router Management System (Cablesight)
Jun 2024 - Aug 2024
Rewrote an existing PHP-based system into a cross-platform React Native application (including web via react-native-web) for managing routers, networks, and customers.
Mobile Crypto Wallet (Gridlock)
Jan 2023 - Feb 2024
Led the development of secure data backup, offline mode, and account recovery features for a self-custodial crypto wallet application.
E-Learning Platform (HSUP)
May 2021 - Jan 2023
Created a high-availability E-learning platform supporting thousands of students, featuring interactive content, online tests, and collaborative tools.
Package Delivery and Tracking System (Viddl)
May 2021 - Jan 2023
A comprehensive package delivery tracking application with real-time map visualization, route optimization, and courier management.
Online Oncological Healthcare Platform (Asseco)
Jun 2019 - May 2021
A specialized healthcare platform enabling doctors to share patient data, request second opinions, and conduct video conferences for oncological treatments.
Skills & Technologies
frontend
backend
tools
other
Get in Touch
Contact Information
Email: krisztwos@gmail.com