Stefan Ginev, Developer in Varna, Bulgaria
Stefan is available for hire
Hire Stefan

Stefan Ginev

Verified Expert  in Engineering

Software Developer

Varna, Bulgaria
Toptal Member Since
May 14, 2020

Stefan is an accomplished and flexible developer who can easily switch between vastly different sets of technologies. During his 13-year career, this helped him learn to quickly adapt to new frameworks, tool sets, and languages while delivering professional quality products. He is a stickler for good UX, so expect beauty, performance, and functionality. His work is reliable, robust, and original. Stefan's current stack of choice is MERN.


Unity, Docker, Three.js, Express.js, MongoDB, Node.js, Angular, React...
React, Three.js, TypeScript, Gatsby, Amazon Web Services (AWS), Jira, Sentry...
PixiJS, JavaScript, TypeScript, Blockchain, EOSIO, Non-fungible Tokens (NFT)...




Preferred Environment

Adobe Photoshop, Docker, Git, Visual Studio Code (VS Code), TypeScript, Firebase, WebGL, Game Development, Web Development, Node.js

The most amazing...

...project I've built is a multi-player game connecting React clients via WebSocket rooms server-side, with a RESTful API for authentication and data persistence.

Work Experience

Software Developer

2009 - PRESENT
  • Created a time-tracking web app in React. The back end is served as a REST API service with MongoDB.
  • Built a self-hosted project management system for developers, integrated with a third-party code IDE (code server) and image editing app (Photopea).
  • Developed an in-browser 3D skeleton animation editor and bundler with project-specific features. The user interface is rendered in React, and the model visualization with Three.js.
  • Devised an asset conversion and bundling tool in Node.js and integrated it with Travis CI for automation to reduce menial tasks in development.
  • Deployed a game content editor in Angular to aid development. It features maps of location nodes, scripts, and a dialog text editor with syntax highlighting and auto-complete via the ACE editor.
  • Built a game content manager rendered with React. It features code editors, GitHub integration, and Google Firebase authentication.
  • Developed a wedding planning app with an editable relation tree for guests and a detailed seating arrangement map.
  • Created a kiosk interface in HTML5 with content manager and weather API integration.
  • Built an MVP in React for a web app with speech-to-text dictation in the browser and text-highlighting for playback progress. The back end is a combination of a REST API and WebSocket connections.
  • Co-developed three multiplayer games aimed primarily at team building and online family activities. The project uses React and Firebase.
Technologies: Unity, Docker, Three.js, Express.js, MongoDB, Node.js, Angular, React, TypeScript, C#, REST APIs, WebSockets, Socket.IO, Firebase, CAPTCHA, GitHub API, Flash, ActionScript 3, Firebase Hosting, Firebase Authentication, Firebase Realtime Database, 3D, 2D Games, 3D Games, Firebase Web SDK, Unity3D, Web Audio, Smart Homes, Internet of Things (IoT), Flash ActionScript, Game Design, Game Development, Game Tools Development, JavaScript, Git, HTML5, Web, WebGL, Multiplayer, Adobe Photoshop, Webpack, PixiJS, GSAP, Web Development, Webhooks, DigitalOcean, Travis CI, Bitbucket API, NGINX, CircleCI,, UglifyJS, SCSS, HTML, ECMAScript (ES6), MERN Stack, jQuery, Jasmine, MySQL, Serverless, Raspberry Pi, CSS, Full-stack, Architecture, Dashboards, Animation, UI Animation, Card Games, Online Games, GUI Animation, GreenSock Animation Platform (GSAP), UI Design, Front-end, Low-code Development, Low Code, Redux, Front-end Development, Back-end, Games, Visual Studio, Web 3.0, Google Cloud Platform (GCP), OpenAI GPT-3 API, Software Architecture, Babylon.js, OpenAI GPT-4 API, Image Generation, Next.js, Tailwind CSS, 3D Character Animation, 3D Animation, 3D Art, NoSQL, ChatGPT, API Development, API Integration, JSON REST APIs, Crypto, Graphical User Interface (GUI), HTML Canvas, HTML5 Canvas, Tuya, Cloud Firestore, OpenAI, SaaS, Material UI, tRPC, Large Language Models (LLMs), Stable Diffusion, Terragen, Technical Art, Asynchronous Programming, GLSL, Graphics Programming, No-code Development, CSS3, CSS3 Animation, HTML5 Animations, Single-page Applications (SPA), CI/CD Pipelines, Web3, Artificial Intelligence (AI), PWA, Full-stack Development

Front-end Developer and 3D Expert

2022 - 2023
  • Developed an app using React, Recharts, and Three.js: the app visualizes recorded scenes and telemetry data from online races. It provides options and tools for users to inspect and judge incident circumstances.
  • Tracked and fixed bugs using Sentry and Jira as reporting tools.
  • Used the MUI framework to develop the app's admin dashboard and lists of online races and tournaments according to Figma designs.
  • Wrote on interpolation logic to fill in missing data on the back-end side (Node.js).
Technologies: React, Three.js, TypeScript, Gatsby, Amazon Web Services (AWS), Jira, Sentry, CSS, WebGL, 3D Animation, API Integration, JSON REST APIs, Graphical User Interface (GUI), HTML Canvas, HTML5 Canvas, SaaS, Material UI, tRPC, GLSL, CSS3, CSS3 Animation, HTML5 Animations, Single-page Applications (SPA), Full-stack Development

Front-end Game Developer

2021 - 2022
  • Planned and developed a blockchain game for the client. Utilized EOSIO and AtomicHub's web APIs to communicate with contracts, sign transactions for in-game actions, and verify NFT ownership.
  • Structured and maintained the centralized part of the game's back end using mainly Firebase Firestore. Items requiring frequent updates were retrieved via Airtable's public API.
  • Used Airtable to administrate items we knew would need frequent updates easily, i.e., system messages and special event banners. Game admins can choose how messages are shown via multi-selection, upload images, and manage status via Kanban view.
  • Oversaw a small team of developers working with me for the client. Prioritized and broke down tasks for bi-weekly feature releases.
  • Automated the production and staging release workflow via GitHub Actions.
  • Used PixiJS as a rendering engine for the world and UI. Wrote custom shaders for the in-game map and visual effects for UI interactions. Ensured the rendering of large animated terrain with low-performance costs.
  • Wrote low-level utilities for the common animation, layout needs, and data services.
Technologies: PixiJS, JavaScript, TypeScript, Blockchain, EOSIO, Non-fungible Tokens (NFT), Firebase, Firebase Web SDK, GSAP, Airtable, Sentry, Continuous Deployment, Node.js, Game Design, Game Development, Game Tools Development, Git, HTML5, Web, WebGL, Multiplayer, Adobe Photoshop, Webpack, 2D Games, Firebase Authentication, Web Development, Firebase Hosting, Postman, HTML, ECMAScript (ES6), Serverless, CSS, Architecture, Animation, UI Animation, Card Games, Online Games, GUI Animation, GreenSock Animation Platform (GSAP), Webpack 4, D3.js, Data Visualization, Front-end, Ethers.js, Web3.js, Front-end Development, Games, Web 3.0, Software Architecture, Technical Leadership, NoSQL, API Integration, JSON REST APIs, Crypto, Graphical User Interface (GUI), HTML Canvas, HTML5 Canvas, Cloud Firestore, Asynchronous Programming, GLSL, Single-page Applications (SPA), Ethereum, CI/CD Pipelines, Web3, Full-stack Development

Software Developer

2020 - 2022
7Mojos / Casualino
  • Joined work on a multi-layered online games project; The front end was developed in TypeScript with a WebGL render engine. The back end was mainly completed in C# and .NET; PostgreSQL is used for all databases.
  • Introduced changes to the build procedure of existing web apps to reduce the final size of scripts and assets and shorten user load-time.
  • Assisted the team in updating the current development flow with modern tools, including Webpack and Terser Minifier.
  • Led the development of games and core SDKs packaged as a single TypeScript monorepo. The front end is rendered with PixiJS 5, a WebGL render engine, and communicates with the back end over custom API.
  • Wrote an automation tool for transforming and combining data between HTML, JSON, YAML, and XLSX (Excel) files.
Technologies: .NET, Webpack, Gulp, Node.js, TypeScript, PixiJS, 2D Games, APIs, Howler.js, GSAP, GreenSock Animation Platform (GSAP), Webpack 4, Monorepos, Game Development, Web Development, Casino Games, Slots, JavaScript, Git, HTML5, Web, WebGL, Adobe Photoshop, HTML, ECMAScript (ES6), PostgreSQL, CSS, Architecture, Animation, UI Animation, Online Games, GUI Animation, UI Design, Front-end, Electron, Front-end Development, Games, Visual Studio, Software Architecture, Technical Leadership, API Integration, JSON REST APIs, Graphical User Interface (GUI), HTML Canvas, HTML5 Canvas, Asynchronous Programming, Graphics Programming, No-code Development

Software Developer

2018 - 2020
Blockchain Solutions
  • Developed multi-threaded programs in Python for scraping messages from public Telegram chats and channels, normalizing data and storing it in Cassandra or Elasticsearch. RabbitMQ was utilized as middle-ware to handle spikes in load.
  • Improved and maintained a collection of web games created with Construct 3. Addressed several bugs and inefficiencies. Integrated custom online leaderboard service and social media actions.
  • Constructed an obfuscation and encryption layer for existing JavaScript game communication with the servers and the accompanying decryption logic in PHP.
  • Wrote single-use bots for transforming or migrating large amounts of existing data during the occasional shifts in the project structure.
  • Developed a highly configurable mock-server tool for easy testing of bot and front-end code by faking situations such as back-end errors, long response times, and bad data.
Technologies: Construct, JavaScript, Google Cloud, Node.js, Python, Git, Firebase, Webhooks, Data Scraping, Scraping, Slack, UglifyJS, Postman, HTML, ECMAScript (ES6), Elasticsearch, PostgreSQL, Python 3, Web Scraping, CSS, Dashboards, Online Games, 2D Games, Firebase Web SDK, Data Visualization, UI Design, Front-end, RabbitMQ, Front-end Development, Back-end, Games, Construct 2, Construct 3, Google Cloud Platform (GCP), Software Architecture, NoSQL, API Development, API Integration, JSON REST APIs, Graphical User Interface (GUI), SaaS, Asynchronous Programming, CSS3, CI/CD Pipelines

Software Developer

2012 - 2018
Bigmage Studio
  • Delivered several apps and games for browsers and mobile in collaboration with the team. Handled visuals, gameplay, and front-end to back-end communication protocols and strategies.
  • Devised a complex mobile billiards app for a foreign market. The project involved real-time physics simulation, low-level shader programming, multiplayer logic in C#, in-app purchases, player progression, and live tournaments.
  • Developed the gameplay section of a casual game for both Android and iOS. Aside from trigonometry, mock-physics, and ads integration, specific work was aimed at adding polish and spectacle to what resulted in one of the firm's most visually engaging projects.
Technologies: Java, ActionScript 3, Adobe AIR, Android, Ionic, C#, APIs, Multiplayer, 3D, Flash ActionScript, Node.js, Game Development, Game Tools Development, JavaScript, Git, Web, 2D Games, Slack, Postman, jQuery, MySQL, CSS, Full-stack, Architecture, Dashboards, Animation, UI Animation, Online Games, GUI Animation, UI Design, Front-end, Front-end Development, Back-end, Games, Software Architecture, 3D Animation, API Integration, JSON REST APIs, Graphical User Interface (GUI), GLSL, Graphics Programming, No-code Development

Prototype for a Web Card Game

A turn-based card game rendered via PixiJs, a WebGL 2D framework, leveraging Airtable as a solution for easy management by storing the data for cards and opponents and tracking ongoing research and work progress.
The app then retrieves necessary data via Airtable's API.

Front End for 3D Visualization of AI-generated Protein Molecules

As the only front-end developer, I developed a single-page web application using the React framework to generate and view protein molecules in 3D. Communication with the back end was resolved through a custom API, and the models were inferred by the client's proprietary machine-learning technology. I also conceptualized, designed, and implemented the app from the ground up with modern build tools and frameworks. I tested and supported several libraries for rendering 3D molecules before settling on the one that best suited the project's requirements. As it was a time-sensitive project, I aimed to balance the rapid development pace and a clean and maintainable codebase. Throughout this project, I gained invaluable insights into the complexities of protein design and the broader scope of bioengineering.

3D Experience (WebGL)

• Independently prototyped a new viewer version using Three.js, focusing on heightened performance and stability and tackled the complex challenge of loading extensive and intricate 3D models, including architectural visualizations and BIM elements like pipes and appliances, through inventive approaches for performant loading and selection mechanisms.
• Took ownership and assisted in enhancing and troubleshooting the existing 3D viewer application, using pure WebGL for rendering without reliance on 3rd-party engines.
• Enhanced camera controls, incorporated animation smoothing, and reworked rendering techniques, significantly elevating the user interaction experience.
• Successfully integrated 2D UI elements into the 3D scene.

VEN Games
A collection of web games similar to and a couple of real-life board games. I laid the project's groundwork and co-developed the games and core SDK. The project is a mono repository, with the logic and front end written in TypeScript and React, while the multiplayer rooms and gameplay updates were achieved using Firebase Realtime Database.

Front End for ML-powered Speech-to-text Dictation App

I built an MVP in React for a web app with speech-to-text dictation in the browser and text highlighting for playback progress. Using a performant machine learning model, the back end combines a REST API and WebSocket connections.

Procedural Interactive Book

A PWA (progressive web application) that aims to present a novel experience, combining the visual minimalism of ''choose-your-own-adventure'' books with the openness of traditional computer games. On the surface, the app is text animated with Three.js and jQuery animations; behind the scenes, it blends scripted events and dialogue with procedural sentence generation (think "online chat-bots") and an AI narrative director orchestrating a modular story at a reasonable pace. AngularJS was used to build both the game client and a custom tool for editing all characters, locations, special events, and dialog/narration snippets.

Collectible Card Game in React

On the client-side, this is a single-page web application written in TypeScript with React for rendering and GSAP combined with regular CSS handling most of the animation. The server consists of a simple Express.js app, utilizing Google's Firebase SDK for authentication and data persistence (Google's Firestore) and the beautiful and open-source Colyseus framework for room management and real-time communication. For administration, I created a card editor as a separate React app that uses simple forms, the ACE editor plugin for writing the card effects with syntax highlighting, and custom autocomplete. I opted to use the GitHub API for saving/loading data with added makeshift change history.

Prototype Flutter App for Wear OS

A small prototype application utilizing built-in speech recognition and text-to-speech to send prompts to ChatGPT and read out the response directly from your watch.

The app was built using Flutter, with minimal UI and animations.


Node.js, React, Three.js, WebGL, GSAP, Firebase Web SDK, Babylon.js, API Development, HTML5 Canvas, jQuery, Bitbucket API, GitHub API, REST APIs, Socket.IO, Web Audio, D3.js, Web3.js, Recharts, Victory


Flash, Adobe Photoshop, Webpack, Git, Visual Studio, Postman, Webpack 4, Firebase Authentication, ChatGPT, NGINX, UglifyJS, CircleCI, Travis CI, Slack, Gulp, Adobe AIR, Lerna, Sentry, Figma, RabbitMQ, Jira, PDB, Construct 2, Construct 3, Terragen


PixiJS, Express.js, Unity, Unity3D, Tailwind CSS, Angular, Bootstrap, Jasmine,, .NET, Ionic, Redux, Electron, Flutter, Next.js, Material UI, tRPC


JavaScript, Flash ActionScript, HTML5, TypeScript, ActionScript 3, CSS, C#, ECMAScript (ES6), HTML, GLSL, CSS3, Python 3, Java, SCSS, Python


Asynchronous Programming, Low-code Development, Continuous Deployment, UI Design, Building Information Modeling (BIM)


Firebase, Visual Studio Code (VS Code), Docker, Web, Raspberry Pi, DigitalOcean, GreenSock Animation Platform (GSAP), Windows, Ubuntu, Android, Blockchain, Amazon Web Services (AWS), Google Cloud Platform (GCP), Ethereum


Firebase Realtime Database, NoSQL, MongoDB, Elasticsearch, PostgreSQL, MySQL, Google Cloud, Cloud Firestore


Game Development, 2D Games, Firebase Hosting, Dashboards, Architecture, Front-end, Front-end Development, Games, Software Architecture, 3D Animation, Graphical User Interface (GUI), Graphics, Full-stack, MERN Stack, Multiplayer, Game Design, Game Tools Development, 3D, APIs, 3D Games, Animation, UI Animation, Card Games, Online Games, GUI Animation, Low Code, Back-end, Technical Leadership, Image Generation, 3D Character Animation, API Integration, JSON REST APIs, Crypto, HTML Canvas, Stable Diffusion, Graphics Programming, CSS3 Animation, HTML5 Animations, Single-page Applications (SPA), CI/CD Pipelines, Artificial Intelligence (AI), Full-stack Development, Web Scraping, Serverless, Construct, Howler.js, Monorepos, Styled-components, Scraping, Data Scraping, WebSockets, CAPTCHA, Smart Homes, Internet of Things (IoT), Webhooks, Web Development, Casino Games, Slots, Non-fungible Tokens (NFT), EOSIO, Airtable, Client-side JavaScript Frameworks, Speech to Text, Data Visualization, Ethers.js, Gatsby, Web 3.0, VictoryChart, 3Dmol.js, NGL Viewer, Mol*, OpenAI GPT-3 API, Wear OS, Android Wear, Speech Recognition, Text to Speech (TTS), OpenAI GPT-4 API, 3D Art, 3D Modeling, Tuya, OpenAI, SaaS, Large Language Models (LLMs), Technical Art, No-code Development, Smart Contracts, Web3, PWA

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.


Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring