Hi, I’m Denis - Full-Stack Developer specializing in mobile apps, mobile games (Unity 2D/3D), and end-to-end product development (frontend + backend + mobile).
🔥 𝐅𝐫𝐞𝐞 𝐑𝐨𝐚𝐝𝐦𝐚𝐩 & 𝐂𝐨𝐧𝐬𝐮𝐥𝐭𝐚𝐭𝐢𝐨𝐧
I offer a free roadmap for your mobile app, mobile game, or full-stack product, outlining architecture, tech stack, and key development steps.
Also available: a free consultation call to discuss your idea and define the best approach.
How I can help (Full-Stack + Mobile Apps + Mobile Games):
Mobile Game Development (Unity 2D / Unity 3D | iOS / Android)
• Full-cycle development (prototype → production → LiveOps)
• Unity 2D / Unity 3D gameplay programming (C#)
• Progression systems, retention mechanics, game economy basics
• Performance optimization (FPS, memory, GC)
• Cross-platform builds (iOS, Android, WebGL)
• Monetization: Ads (AppLovin MAX, Google Ads), IAP, subscriptions
• Analytics & attribution (Firebase, Adjust)
Mobile App Development (React Native)
• Cross-platform apps (React Native / Expo)
• Offline-first architecture, sync systems
• Push notifications, deep linking, background tasks
• Performance optimization (startup time, rendering, memory)
• In-app purchases, subscriptions, paywalls
• Release pipelines (App Store / Google Play)
Full Stack Web Development (Next.js, React, Node.js):
• Full-stack (frontend + backend) development
• Next.js / React, Node.js / NestJS
• REST / GraphQL, WebSockets
• PostgreSQL, Redis
• Auth, dashboards, admin panels
• Performance, SSR/SSG, scalable architecture
Our Projects & Results:
💥 KFC Fake Games – Global Campaign
→ Delivered 4 mobile games in 2 months (iOS & Android)
→ Full-cycle development + optimization + release
💥 Renovation Empire – Mobile Game
→ Built scalable gameplay systems & retention mechanics
→ Performance-optimized architecture
💥 GIBBON Training App
→ Gamified mobile app with real-world use
→ Stable, scalable product architecture
Why clients hire me:
• I build full-stack products, not отдельные куски
• I combine Unity (2D/3D) + React Native + Backend in one system
• I think about scale, performance, and monetization from day one
• Clean, maintainable, production-ready architecture
• Clear communication, fast execution, no chaos
Tech Stack Summary:
Game Dev: Unity 2D, Unity 3D, C#, Addressables, UniTask, VContainer, R3
Mobile Apps: React Native, Expo
Frontend: React, Next.js
Backend: Node.js, NestJS, REST, GraphQL, WebSockets
Data: PostgreSQL, MongoDB, Redis
Monetization & Analytics: Firebase, Adjust, AppLovin MAX, Google Ads
Architecture: SOLID, Clean Architecture, event-driven systems
Keywords:
Full stack development, mobile app development, mobile game development, Unity 2D, Unity 3D, React Native, Next.js, React, Node.js, NestJS, REST API, GraphQL, WebSockets, Clean Architecture, SOLID, scalable architecture, Firebase, Adjust, monetization, in-app purchases, subscriptions, real-time systems
Game Development
Game Design
Game
Unity
Video Game
C#
Mobile Game
Game Prototype
Android
iOS
UX & UI
AR & VR
VR Application
Animation
Mobile Game Development
AR & VR Development
3D Modeling
3D Animation
Game Art
3D Design
Alexey I.
Warsaw, Poland
$30/hr
4.7
22 jobs
Hi 👋 I’m a Unity programmer with 12+ years in game development.
I build games from prototype to full release across mobile, WebGL, and PC, and I’m equally comfortable joining mid-project to fix critical issues, optimize performance, or stabilize unstable builds.
Whether it’s a hyper-casual prototype, a mid-core RPG, or a multiplayer live-ops project — I deliver clean code, smooth gameplay, and reliable results. 🚀
🔹 What I do best
Full-cycle Unity development — take your project from concept and prototype to launch-ready game
Cross-platform builds — mobile, WebGL, PC, optimized for performance and memory
Multiplayer & live-ops systems — Photon, PlayFab, analytics, monetization, retention improvements
Expert bug fixing & optimization — tricky crashes, memory leaks, edge cases, build size reduction
Legacy code rescue — stabilize and refactor outdated, messy, or incomplete projects
🔹 Work style
Clear estimates and timelines before starting
Regular progress updates with measurable results (daily or weekly)
Open, fast communication; adapt quickly to feedback and changing priorities
Focus on delivering working, polished, release-ready projects
🔹 Why work with me
12+ years in game development (indie & enterprise)
Ability to deliver complete games for any genre and platform
Clean, maintainable code designed for long-term development
Strong debugging & optimization skills — fix critical bugs, improve performance, and reduce build sizes
Trusted to rescue mid-project when things aren’t working, without slowing the schedule
Clients praise my speed, reliability, and ability to deliver under tight deadlines
🛠 Tech Stack
Unity, C#, Addressables, Photon, PlayFab, DOTS, ShaderGraph, Firebase, C++, Ruby, Objective-C, SQLite, IronSource, JSON, Protobuf, dev2dev, Appsflyer, Game Analytics, Tenjin, IAPs, ByteBrew, Yandex SDK, React, JavaScript, Google Play Services, Zenject
🧠 Selected Results
PUA — Date Game & Love Stories: Created a custom scenario tool (cut content time 2h → 10min), implemented AI bots, fixed major production issues
Idle Spellbound Mage RPG: Reduced build size by 75%, enabling a successful WebGL port without losing features
Nanomedix: Transformed unstable, incomplete project into a release-ready product through stabilization, optimization, and feature expansion
Zombie Shop: Solved elusive critical bugs QA couldn’t reproduce, stabilizing a high-profile release
Merge Islanders: Enhanced core systems & performance; updates doubled revenue according to publisher
💬 Let’s talk
Need help with full-cycle Unity development, optimization, bug fixing, or launching a complete game?
I’m available for consultations, quick fixes, or long-term collaborations — let’s make your project a success.
Game Development
Game Design
Unity
C#
Game Development Bug Fix
Game Prototype
Research & Development
Multiplayer
Photon Unity Networking
Game UI/UX Design
Game Mechanics
Mobile Game Development
Mobile Game
WebGL
AR & VR Development
Piotr D.
Czestochowa, Poland
$45/hr
5.0
37 jobs
✅ TOP RATED Developer
Greetings! With over 12 years of experience in Unity development and 4 years in web development, I'm a passionate programmer dedicated to crafting exceptional games and websides. My diverse skillset encompasses the entire development process, from designing engaging gameplay mechanics to optimizing performance across various platforms
✅Solid 12 years of experience with Unity3D and 3 years in Web development
🎓 Master degree in Software Engineering.
🔥 Contributed to over 20 projects, also for iOS and Android platforms.
✅ Creating games from scratch through the entire production cycle, including publishing in stores.
✅ Enhancing, optimizing, and completing games developed by others
✅ Designed and developed various games for companies and individuals.
🔥UNITY3d SKILLS:
➡️ Shaders, Cg/hlsl, URP/HDPR
➡️ Mobile (Android + Ios)
➡️ Animator, Tmpro, Ui
➡️ Profiling, asset optimalization,
➡️ Game development from inception to publication
➡️ Game design
➡️ In-app Purchases, Test Framework, Localization, Photon Networking, Admob, Facebook, Firebase, Playfab, PlayLevel, Analytics,
🔥WEB SKILLS:
➡️.NET Core/.NET MVC
➡️React
➡️Angular
➡️TS/JS
➡️Stripe
➡️Entity Framework
➡️Docker
🔥OTHER SKILLS🔥:
➡️ Git, SVN
➡️ C#, C++, PHP
➡️ Blender
➡️ HTML, ASP.NET Core MVC
➡️ CSS, Entity Framework
... and many more.
Game Development
Unity
Angular
SQLite
Programming Bug Fix
Blender
Web API
.NET Core
SQL
AWS Fargate
Web Application
Web Service
Web Testing
Entity Framework
SignalR
Lukasz K.
Gdańsk, Poland
$56/hr
4.9
101 jobs
Hello World
I am a game developer generalist, tools and bot coder with 10+ years of freelancing experience.
I've worked solo and in teams on 2D/3D, VR, single and multiplayer games. In recent years I've specialized in Unreal Engine but I've also used Unity and other tech in the past. Besides that I also know my way around automation (Bots for websites, games, desktop programs, mobile apps) and music related tools (Midi/Arduino).
If you have interesting project then don't hesitate to contact me.
cheers
Game Development
Game Design
Unity
Virtual Reality
Unreal Engine
Godot
C++
MIDI
Bot Development
OpenCV
Automation
Pascal
Blueprint Style
Prototyping
Jakub K.
Olsztyn, Poland
$42/hr
5.0
31 jobs
🎮 Passionate JavaScript Game Wizard
Creating Playable Ads and HTML5 Games with WebGL libraries: BabylonJS, Pixi.js, Three.js
GreenSock(GSAP), Plank.js, Cannon.js, and other physic engines.
What I Do:
✨ Playable Ads Development: Transforming concepts into interactive playable ads that capture attention and drive engagement.
🕹️ HTML5 Game Development: Crafting seamless and addictive games using cutting-edge technologies and creativity.
🎨 Graphics and Asset Creation: Skilled in creating stunning 3D models using Blender and crafting intricate 2D assets with graphic software.
🚀 Expertise in TypeScript, Three.js, Pixi.js, GreenSocket, and many other JS libraries: Leveraging the power of these tools to create visually stunning and responsive games and ads.
Why Choose Me:
🌟 3 years of experience making HTML 5 games
💡 12 years of professional experience as a FullStack Developer with technology like React, Node.js, PHP, MySQL, webpack,
🤝 Self-starter developer with graphic design skills to speed up the process
"I don't just create games; I craft immersive experiences that leave a lasting impression. Let's turn your ideas into interactive reality!"
Ready to level up your Playable Ads or HTML5 games? Let's connect and discuss how I can transform your vision into captivating digital experiences. Feel free to reach out, and let's embark on a journey of creativity and innovation together!
TypeScript
PixiJS
Three.js
WebGL
HTML5 Canvas
Babylon.js
Adam W.
Radzanowo, Poland
$5/hr
5.0
6 jobs
I am a starting game developer where i myself made some games where I used my own art that I created in libresprite, and recently I started using Inkscape for vector art
Game Development
Game Design
Pixel Art
Game Art
Video Editing
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