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Balazs Welker, Software Developer in Vienna, Austria
Balazs Welker

Software Developer in Vienna, Austria

Member since April 27, 2022
Balazs boasts a remarkable 12 years of IT industry experience, excelling in various roles, including software engineer, game developer, and project manager. Balazs specializes in web development and is an expert in React, React Native, and TypeScript. His deep full-stack experience includes working with Node.js, Express.js, PostgreSQL, MongoDB, GraphQL, and NestJS. Balazs is also well-versed in 3D and AR/VR using Unity and Unreal Engine. He was awarded Forbes 30 under 30.
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Portfolio

Experience

Location

Vienna, Austria

Availability

Part-time

Preferred Environment

MacOS, Visual Studio Code (VS Code), Git, Windows, Unity3D, React, React Native

The most amazing...

...thing I've developed as an engineer is the Robonaut 2 Simulation for NASA.

Employment

  • Leap Motion Developer

    2023 - 2023
    Creatorz Deitz Sarl
    • Responsible for creating a manager script and for tracking the hand movement with Ultraleap.
    • Created a custom sequencer to play videos using images stored in arrays.
    • Improved the performance of the source code, optimized the project, and create the final builds.
    Technologies: Leap Motion, C#, C, Unity, Unreal Engine, Gamification, Software Design

  • Senior Full-stack Developer

    2022 - 2023
    Hommz Technologies Ltd
    • Worked on a complex, large-scale application as part of my role as a React and Node.js senior full-stack developer.
    • Implemented new features into the micro-service back-end and improved the codebase using NestJS and Express (Node.js).
    • Worked on the front-end side of their web application and an admin dashboard using React.
    Technologies: React, Node.js, PostgreSQL, Full-stack, TypeScript, REST APIs, User Interface (UI), Microservices, Software Architecture, Kubernetes, Docker, Architecture, JavaScript, jQuery, Bootstrap, Progressive Web Applications (PWA), MERN Stack, Agile Software Development, REST, Jest, DOM, API Integration, Mobile Apps, Technical Architecture, Web Forms, Styled-components, Databases, Software Design

  • External Screener

    2022 - 2022
    Toptal
    • Prepared for and interviewed new candidates coming to Toptal.
    • Prepared and developed internal documents and tasks.
    • Interviewed more than 300 candidates in a quarter.
    Technologies: JavaScript, React, Node.js, Express.js, GitLab CI/CD

  • Senior Front-end Engineer (React Native)

    2022 - 2022
    The Poolit (via Toptal)
    • Built the entire architecture of a web application.
    • Served as a senior front-end engineer and integrated various features, such as identity verification, into the application.
    • Worked on deploying the application on the App Store.
    • Integrated the feature into the mobile application.
    Technologies: React Native, TypeScript, Jest, Web Applications, Proof of Concept (POC), Express.js, Swagger, Automated Testing, REST APIs, GitLab CI/CD, Google Pay, CI/CD Pipelines, GitHub, Figma, Git, REST, Redux Thunk, React Redux, Mobile Apps, CSS, Visual Studio Code (VS Code), MacOS, React Apollo, User Interface (UI), Software Architecture, JavaScript, jQuery, Bootstrap, Progressive Web Applications (PWA), Management, Team Leadership, Google Cloud Platform (GCP), MERN Stack, Python, Electron, Agile Software Development, DOM, API Integration, Technical Architecture, Web Forms, Minimum Viable Product (MVP), Styled-components, Technical Leadership, Databases, Software Design

  • Flutter Developer

    2022 - 2022
    One4all Finland Oy
    • Took responsibility for creating the entire mobile application UI part using Flutter for a real estate application.
    • Used Flutter and integrated the web view version to support desktop users.
    • Followed the Web Content Accessibility Guidelines (WCAG).
    Technologies: Flutter, APIs, WCAG 2, Web Applications, Proof of Concept (POC), Express.js, REST APIs, GitHub, Figma, Git, REST, Visual Studio Code (VS Code), MacOS, User Interface (UI), Management, Team Leadership, Agile Software Development, API Integration, Mobile Apps, Technical Architecture, Web Forms, Minimum Viable Product (MVP), Styled-components, Technical Leadership, Databases, Software Design

  • React Native Developer

    2022 - 2022
    UX Integrated Inc.
    • Was responsible for integrating the Firebase Push Notification service into the Norton Transport mobile application.
    • Implemented the feature in a React Native mobile application.
    • Contributed to the Firebase Push Notification that was used on iOS and Android.
    Technologies: React Native, iOS, Android, Mobile Apps, Redux, Redux-Saga, Ruby on Rails (RoR), Firebase Cloud Messaging (FCM), Firebase, Web Applications, Proof of Concept (POC), Express.js, REST APIs, Google Pay, GitHub, Git, REST, Redux Thunk, React Redux, Visual Studio Code (VS Code), MacOS, User Interface (UI), JavaScript, jQuery, MERN Stack, Agile Software Development, DOM, API Integration, Mapbox, Technical Architecture, Web Forms, Minimum Viable Product (MVP), Styled-components, Twilio, Twilio API, Technical Leadership, Logistics, Databases, Software Design

  • Full-stack Developer (Node.js and React)

    2022 - 2022
    Rollup Systems Inc
    • Created a back-end service using NestJS for a systems engineering product.
    • Created a microservice back end for the Rollup web application.
    • Used NestJS, PostgreSQL, and Docker technologies to create the service and AWS for deployment.
    Technologies: Node.js, React, MobX, PostgreSQL, Amazon Web Services (AWS), Redux, NestJS, Web Applications, Proof of Concept (POC), Express.js, Swagger, Automated Testing, REST APIs, Full-stack Development, CI/CD Pipelines, GitHub, Git, Docker, Kubernetes, WebSockets, REST, Redux Thunk, React Redux, Visual Studio Code (VS Code), MacOS, Mathematics, React Native, User Interface (UI), PLC, Microservices, Software Architecture, C#, JavaScript, jQuery, NGINX, Cloudflare, Progressive Web Applications (PWA), Python, Management, Team Leadership, Google Cloud Platform (GCP), MERN Stack, Electron, Agile Software Development, Jest, DOM, Heroku, API Integration, Technical Architecture, Data Visualization, Web Forms, Minimum Viable Product (MVP), Styled-components, Technical Leadership, Databases, Software Design, Startups

  • Lead Full-stack Engineer

    2021 - 2022
    Hungarian Police
    • Worked on the National Police Headquarters - National Accident Prevention (Országos Rendőr-főkapitányság - Országos Balesetmegelőzés ORFK-OBB) OBBPoint app as a lead full-stack engineer. It’s a mobile app for speed tracking for the Hungarian police.
    • Spearheaded the entire project starting from the planning to the publishing.
    • Worked on the UI/UX of the mobile application and the official website, based on my previous experiences.
    • Prepared the REST API and the PostgreSQL database as the lead with experience in back-end development.
    • Managed the mobile application in Unity and the integration into React Native to create a background service to do the speed calculation based on the device movement and GPS position.
    • Collaborated with the marketing team to prepare the marketing and create the official videos.
    • Worked with the QA testers on the closed release of the application at the end of the project.
    Technologies: React, React Native, Unity, 3D, GPS, Location Tracking, Google Maps API, Kubernetes, Docker, TypeScript, Firebase, CTO, Leadership, Node.js, Mobile, SQL, MySQL, HTML, Front-end, Back-end, iOS, Android, Agile, Scrum, APIs, MongoDB, Flutter, Sass, SCSS, Next.js, Amazon Web Services (AWS), Full-stack, Architecture, Web, Roadmaps, Milestones, JavaScript, DevOps, Mobile Development, PHP, Expo, CSS, NoSQL, NestJS, Web Applications, Proof of Concept (POC), Express.js, Storybook, Swagger, REST APIs, Full-stack Development, Google Pay, CI/CD Pipelines, GitHub, 3D Art, Figma, Unity3D, Git, REST, Redux Thunk, React Redux, Adobe Photoshop, Substance Painter, Visual Studio Code (VS Code), MacOS, GraphQL, GLONASS, GNSS, GIS, Mathematics, User Interface (UI), Desktop App Development, Inverse Kinematics, Microservices, Software Architecture, C#, jQuery, Bootstrap, NGINX, Cloudflare, Progressive Web Applications (PWA), Python, Management, Team Leadership, Google Cloud Platform (GCP), MERN Stack, Agile Software Development, Jest, DOM, Heroku, API Integration, Mobile Apps, Mapbox, Technical Architecture, Web Forms, Minimum Viable Product (MVP), Styled-components, Twilio, Twilio API, Technical Leadership, Unity2D, Artificial Intelligence (AI), Unity SDK, Databases, Game Development, Game Design, Unity Game Assets, Gamification, Software Design

  • Lead Full-stack Engineer

    2021 - 2022
    NeuraERP
    • Worked as a lead full-stack engineer for freight management ERP software.
    • Developed core and mobile applications with React and React Native.
    • Stored the sensitive data in Blockchain using Hyperledger Fabric.
    • The project has an AI feature to optimize the routes using Google Maps and HERE Maps API.
    • Created an invoicing and payroll system as one of the core tasks.
    Technologies: React, React Native, React Redux, Redux Thunk, Pusher, React Apollo, GraphQL, PostgreSQL, REST, WebSockets, Artificial Intelligence (AI), Finance, Invoicing, Payroll & Benefits, Blockchain, TypeScript, Firebase, CTO, Leadership, Node.js, Mobile, SQL, MySQL, HTML, Front-end, Back-end, iOS, Android, Agile, Scrum, APIs, MongoDB, Sass, SCSS, Next.js, Amazon Web Services (AWS), Full-stack, Architecture, Web, Roadmaps, Milestones, JavaScript, DevOps, Mobile Development, PHP, Expo, CSS, NoSQL, Tailwind CSS, NestJS, Web Applications, Proof of Concept (POC), Express.js, Storybook, Swagger, Automated Testing, REST APIs, Full-stack Development, Geocoding, Geolocation, GitLab CI/CD, Google Pay, Apple Pay, Stripe, CI/CD Pipelines, GitHub, 3D Art, Figma, Git, Docker, Kubernetes, Google Maps API, Location Tracking, Visual Studio Code (VS Code), MacOS, GLONASS, GNSS, GPS, GIS, Mathematics, User Interface (UI), Desktop App Development, Microservices, Software Architecture, C#, QuickBooks API, QuickBooks Online, jQuery, Bootstrap, NGINX, Cloudflare, Progressive Web Applications (PWA), Python, Management, Team Leadership, Google Cloud Platform (GCP), MERN Stack, Electron, Agile Software Development, Jest, DOM, Heroku, API Integration, Mapbox, Technical Architecture, Data Visualization, Web Forms, Minimum Viable Product (MVP), Styled-components, Twilio, Twilio API, Technical Leadership, Logistics, Databases, Software Design, Startups

  • Principal Full-stack Engineer

    2021 - 2021
    OBS Financial
    • Created the architecture of the entire application, including the mobile app, web app, and admin dashboard.
    • Developed the signature system to digitally sign and forward documents.
    • Implemented Twilio to the admin dashboard and client-side application for the two-factor authentication and managing SMS service to notify clients.
    • Created the call system feature that the in-house team members used to contact the clients via the admin dashboard.
    Technologies: React Native, React, Node.js, PostgreSQL, NestJS, Next.js, Twilio, Twilio API, JavaScript, Amazon Web Services (AWS), Software Architecture, Technical Leadership, Databases, Software Design

  • Senior Full-stack Engineer

    2021 - 2021
    3DQR
    • Worked as a senior full-stack engineer with Unity and React to create the necessary parts of the platform.
    • Managed the Unity project, the scene setup, 3D models, and animations.
    • Created a working MVP with the core features and scene as the target task.
    Technologies: 3D, 3D Modeling, 3ds Max, 3D Product Modeling, C#, Unity, React, Mobile Apps, Augmented Reality (AR), TypeScript, CTO, Leadership, Node.js, Mobile, SQL, HTML, Front-end, iOS, Android, Agile, Scrum, APIs, Sass, SCSS, Amazon Web Services (AWS), Full-stack, Architecture, Web, Roadmaps, Milestones, JavaScript, DevOps, Mobile Development, Expo, CSS, ARKit, Proof of Concept (POC), Full-stack Development, GitHub, 3D Art, Git, Adobe Photoshop, Substance Painter, Visual Studio Code (VS Code), React Native, User Interface (UI), Desktop App Development, Inverse Kinematics, MERN Stack, Agile Software Development, REST, Unreal Engine, Blueprint, API Integration, Technical Architecture, Minimum Viable Product (MVP), Technical Leadership, Unity3D, Unity2D, Unity SDK, Databases, Game Development, Game Design, Unity Game Assets, Software Design, Startups

  • Senior Front-end Developer

    2020 - 2021
    Panasonic
    • Worked as front-end and Unreal Engine 4 developer.
    • Created the Panasonic Virtual Experience and the official video of IACP 2020 as my main projects.
    • Used Unreal Engine 4 and motion capture technologies to capture the animations and prepare them for the virtual event.
    • Prepared the scenes and the interactions with them using C++ as the Unreal Engine 4 developer.
    Technologies: Unreal Engine 4, React, 3ds Max, 3D Modeling, Quixel, CTO, Leadership, Node.js, HTML, Front-end, Agile, Scrum, Sass, SCSS, Amazon Web Services (AWS), Web, Roadmaps, Milestones, JavaScript, CSS, Proof of Concept (POC), Git, Visual Studio Code (VS Code), User Interface (UI), Agile Software Development, REST, Unreal Engine, Blueprint, API Integration, Technical Architecture, Minimum Viable Product (MVP), Technical Leadership, Game Development, Game Design, Unity Game Assets

  • UI/UX and Senior Front-end Developer

    2016 - 2020
    Alibre
    • Worked as a UI/UX designer and front-end developer.
    • Created the user interface and user experience for the Alibre application.
    • Built more than 1,000 icons for the Alibre software as one of my main tasks.
    Technologies: Adobe Illustrator, Adobe Experience Design (XD), CTO, Leadership, Front-end, Agile, Scrum, SCSS, Amazon Web Services (AWS), Proof of Concept (POC), 3D Art, User Interface (UI), Agile Software Development, Technical Architecture

  • Brand Hero

    2019 - 2019
    OTP Bank
    • Acted as the hero, cheek of the bank, of OTP Bank.
    • Attended several conferences and talked about entrepreneurship for the younger generation.
    • Participated in the media, TV, and commercial advertisements as the cheek of the bank.
    Technologies: Branding, B2C Marketing, Conference Speaking, Agile, Scrum

  • Senior 3D Modeler

    2015 - 2016
    NASA
    • Worked on NASA's Robonaut 2 project as a senior 3D modeler.
    • Created simulation models for hand and grip simulations.
    • Used 3ds Max and Substance Painter for my daily tasks.
    Technologies: 3D, 3D Modeling, 3D Product Modeling, Agile, Scrum

Experience

  • Robonaut 2 Simulation for NASA

    As a senior 3D modeler, I worked on NASA's Robonaut 2 project.

    I created simulation models for hand and grip simulations using 3ds Max and Substance Painter and helped integrate them into the simulation.

  • UI/UX and Front-end Development for Alibre
    https://alibre.com

    Worked as a UI/UX designer and front-end developer for Alibre. Created the user interface and user experience for the Alibre applications. Built more than 1,000 icons for the Alibre software as one of my main tasks.

  • IACP 2020 for Panasonic
    https://na.panasonic.com/us/event/iacp-2020

    Oversaw and participated in the creation of the marketing videos for the IACP 2020 virtual experience event using Unreal Engine 4, 3Ds Max, and motion capture technologies. Created 3D models and characters, managed Unreal Engine scenes, and created the interactions using Blueprint and C++.

Skills

  • Languages

    C#, JavaScript, TypeScript, GraphQL, CSS, SQL, HTML, Sass, SCSS, Python, PHP, C, C++

  • Frameworks

    Redux, React Native, Unreal Engine 4, Unity, Unity3D, Next.js, NestJS, Jest, ARKit, Express.js, Swagger, Bootstrap, Flask, Electron, Unreal Engine, Blueprint, Unity2D, Flutter, Tailwind CSS, Ruby on Rails (RoR)

  • Libraries/APIs

    React, REST APIs, Stripe, Node.js, QuickBooks API, jQuery, Twilio API, React Redux, Pusher, Google Maps API, MobX, Redux-Saga

  • Tools

    React Apollo, Figma, GitHub, Geocoding, Expo, NGINX, Unity SDK, GitLab CI/CD, GIS, Adobe Illustrator, Adobe Experience Design (XD), 3ds Max, Quixel, Substance Painter, Adobe Photoshop, Redux Thunk, Git, Firebase Cloud Messaging (FCM)

  • Paradigms

    REST, Agile, Scrum, Mobile Development, Automated Testing, Desktop App Development, Microservices, Management, Agile Software Development, Gamification, DevOps

  • Platforms

    Mobile, iOS, Android, Amazon Web Services (AWS), Web, Google Cloud Platform (GCP), Heroku, Mapbox, Twilio, Firebase, MacOS, Visual Studio Code (VS Code), Blockchain, Kubernetes, Docker, Windows

  • Storage

    MySQL, MongoDB, NoSQL, Web Forms, Databases, PostgreSQL

  • Other

    3D, Mobile Apps, Augmented Reality (AR), Artificial Intelligence (AI), 3D Art, Geolocation, CTO, Leadership, Front-end, Back-end, Full-stack Development, APIs, Full-stack, Architecture, Roadmaps, Milestones, Web Applications, Proof of Concept (POC), Storybook, User Interface (UI), Inverse Kinematics, PLC, Software Architecture, QuickBooks Online, Cloudflare, Progressive Web Applications (PWA), Team Leadership, MERN Stack, DOM, API Integration, Technical Architecture, Data Visualization, Minimum Viable Product (MVP), Styled-components, Technical Leadership, Logistics, Game Development, Game Design, Unity Game Assets, Software Design, Startups, CI/CD Pipelines, Apple Pay, Google Pay, Mathematics, GPS, GNSS, GLONASS, 3D Modeling, 3D Product Modeling, Software Development, IT Project Management, Finance, WebSockets, Invoicing, Payroll & Benefits, Location Tracking, Branding, B2C Marketing, Conference Speaking, Motion Capture, WCAG 2, Leap Motion

Education

  • Bachelor's Degree in Civil Engineering
    2014 - 2018
    Budapest University of Technology and Economics - Budapest, Hungary

Certifications

  • Forbes 30 Under 30
    MAY 2018 - PRESENT
    Forbes

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