Real uniforms, raymarched in WebGL2. Drag them.
Native mobile, Unity real-time 3D, and full-stack SaaS. Eight years, 500k+ downloads, 35k monthly users, and an enterprise app whose mobile UI/UX I redesigned and implemented natively on iOS and Android. I build with AI the way a senior engineer should: directing it, verifying it, and shipping in weeks what used to take a team a quarter.
Extensive interactive 2D and 3D work
Mobile is my specialty. Most of the games in the portfolio below are Unity titles I built and shipped to the App Store and Google Play myself. The ones I've joined include a racing title I led past 500,000 downloads and an anatomy and pathology app I reworked (interface, auth, backend) that now serves 35,000 monthly users.
The interface is where I'm most often brought in. Most recently, for an enterprise client, I redesigned and implemented their mobile app's UI/UX natively on iOS and Android: the interaction model, the flows, the screens, the performance. Before that, a puzzle game went from fragmented to shippable by rebuilding how it felt under your thumb.
And I own what comes after launch: store releases, staged rollouts, analytics and attribution, crash triage, and the live operations that keep an app running and its ratings up.
Apps I keep live on the storesEight years of Unity under a frame budget, most of it on mobile, where the rule was simple: 60 FPS on mid- and low-end phones or it doesn't ship. I led a racing title past 500,000 downloads, engineered its multiplayer, and adapted 3D vehicle physics to survive network synchronisation.
The biggest build is my MORPG prototype: six months on a scalable, data-driven online game. Addressables streaming, PlayFab and Azure Functions for auth, profiles and economy, Photon Fusion 2 for players, AI enemies, synced combat and chat, and an architecture designed for thousands of zones, items and live events. Playable on desktop, mobile and WebGL with keyboard, controller and touch.
Underneath: custom cel and water shaders, a compute-shader volumetric fog system, a motion-matching controller with tooling to bake animations onto any humanoid rig, and the draw-call and triangle budgets that hold the frame rate. Most of it written by hand, before AI tooling existed.
See the MORPG prototype Game portfolioMulti-tenant architecture, authentication and authorisation, backend APIs, retrieval and vector search, cloud infrastructure and production deployment. The same discipline as shipping a mobile app; it just runs on a server.
Two AI-native products in build. ReadyToEdit I build solo: LLM drafting grounded in cited evidence, semantic search with tenant isolation, review workflows, scheduled ingestion. MasteryGraph I co-founded with two partners: AI Socratic tutoring over a prerequisite graph. In both, AI is in the architecture, not bolted on. Not a chatbot on a landing page. Working software.
This is also where AI changed how I work. One senior engineer directing AI tooling now ships what used to need a small team, and I bring that speed to every engagement with the code review and architecture judgement that makes it safe. If an AI prototyping tool got you most of the way and then broke, I finish it properly: real auth, real backend, real performance.
I'm Rafael Zuniga, a senior engineer who ships across three surfaces: native mobile, real-time 3D, and SaaS. Same standard on all of them. The interface has to feel right, it has to be fast, the backend has to hold, and it has to keep running after launch.
Most of my 8+ years have gone into products with real users. I led a racing title past 500,000 downloads. I reworked an anatomy and pathology app (interface, auth, backend) that now serves 35,000 monthly active users. Most recently I rebuilt the UI/UX of an enterprise mobile app, natively on iOS and Android, from the ground up.
I wrote an enormous amount of code before AI existed. Most of the games on this page were built by hand, which is how there are so many of them, and it is why AI works for me the way it does. I adopted it early and seriously, and I use it the way a senior engineer should: to move fast on the parts that don't need me, so my judgement goes where it counts. I've also shipped AI-native products, not just used AI to write code. That combination is why one engineer can now deliver what a small team used to.
Three surfaces, one standard: it ships, it's fast, and it holds up with real users.
Handling technical publishing, updates, live ops, and maintenance on Google Play & App Store
Comprehensive anatomy and pathology learning application featuring 3,500+ questions across 26 sections. Enhanced the existing app with improved UI/UX, performance optimizations, authentication systems, and backend integrations. Achieved 35k MAU since my contributions in 2025.
Led development of Off-Road Champion, a feature-packed off-road racing game with 500k+ downloads. Integrated critical SDKs (analytics, ad mediation, attribution, push notifications), engineered multiplayer mode, adapted 3D vehicle physics for multiplayer synchronization, and integrated Invector's third-person controller.
Joined an existing puzzle app with solid mechanics but fragmented UX. Redesigned gameplay input to make selecting, rotating, and placing pieces intuitive and enjoyable. Reworked interactions, built missing UI, unified flows, and polished it into a cohesive, shippable product.
Projects I've built from the ground up across mobile, multiplayer, and casual gaming
A dynamic 2D shooter mobile game featuring block-based map arenas, customizable 3-part spaceships, and strategic drone systems with five unique types. Players engage in progressively challenging missions, unlock rewards through a chest system, and enhance gameplay with intuitive touchscreen controls and incremental difficulty scaling.
A thrilling 2D shooter where players build modular spaceships, battle in real-time multiplayer arenas, and unlock powerful upgrades. Featuring dynamic gameplay, diverse game modes, and cutting-edge physics, it offers endless opportunities for strategy and customization.
An addictive arcade game featuring vibrant themes, block-stacking mechanics, and endless challenges. Quirky characters, customizable features, and dynamic stages create a playful blend of strategy and timing.
A single-player word game where players place letters on a constantly shifting board, challenging their skills to form words and stay in the game as long as possible!
A classic dominoes experience where players face a CPU opponent with adjustable difficulty. Featuring quick, strategic matches and a sleek, intuitive interface, it's perfect for sharpening skills or unwinding with a relaxing game.
A vibrant bubble shooter game where players aim, match, and pop bubbles to clear levels. With intuitive controls and satisfying mechanics.
A 3D runner with a quadruped character racing through an infinite, curved world. Featuring procedural levels and enemies resulting in a fast-paced challenge.
A challenging space puzzle game set in a dynamic, ring-filled environment where fuel management and precise navigation are essential for success.
A lively arcade game where players launch and bounce their character across a whimsical candy themed landscape. Fun, fast-paced, and endlessly entertaining.
A 3D kitchen environment featuring a fly with movement data from a Python simulation, bridged into Unity via UDP. Demonstrates real-time data integration and procedural animation techniques.
A 2.5D action game built with LibGDX featuring 3D models integrated onto 2D assets. Includes 60 uniquely designed levels, three wizards with distinct abilities, diverse spell attacks and boosts, AI-driven enemies with state machines, progressive stat system, and in-app purchases.
Stylized horror prototype with custom cel shading
An atmospheric game prototype built in Unity (URP) to explore foundational game elements: visual style, mood, and core mechanics.
🎨 Environment & Visual Style – Designed a central environment with detailed terrain sculpting, texturing, and asset placement. Developed a custom cel shader to achieve a unique stylized aesthetic that sets the visual tone.
🎥 Dynamic Camera System – Built a flexible system that transitions between three camera modes (first-person, third-person, and fixed cinematic angles) as part of exploring different gameplay perspectives.
💧 Custom Shaders – Implemented custom water shaders for realistic pond/river effects and compute-based volumetric fog system for immersive environmental depth. Optimized render calls and triangle count to maintain 60+ FPS on modest hardware.
🎮 Motion Matching Controller – Built a custom motion matching solution with tools to bake animations into any new humanoid rig for natural character movement.
A shorter experiment: an interactive 3D scene built with Three.js.
An interactive 3D forest scene built with Three.js featuring:
🌳 Foliage System – Dynamic tree and vegetation rendering with realistic placement and variety.
✨ Particle Systems – Ambient effects including stars, shooting stars, and fireflies for atmospheric depth.
🎮 Animated 3D Character – Fully rigged and animated character model integrated into the scene.
🎛️ Real-time Interface – Interactive controls for manipulating scene elements and parameters on the fly.
This 6-month project showcases my expertise in full-stack game development, scalable system design, and real-time multiplayer infrastructure. Built with a top-tier tech stack integrating cloud services, efficient asset management, and real-time networking.
At its core, this project is a scalable, data-driven Online Game powered by:
🔗 Addressables – Efficient asset streaming & memory management, ensuring seamless world transitions and content scalability.
🛠 PlayFab & Azure Functions – Robust backend for authentication, player profiles, economy systems (Economy V2), and data persistence.
⚡ Photon Fusion 2 – High-performance networking for players, AI-driven enemies, synchronized combat, in-game chat, and more.
🌎 Scalable MMO Architecture – Designed for thousands of zones, items, enemies, persistent player data, live events, and ongoing content expansions.
🎮 Cross-platform Compatibility – Playable in Desktop, Mobile and WebGL with keyboard & mouse, controllers and touchscreen devices.
Every aspect of this project reflects my ability to design, build, and finalize production-ready game systems, making it the definitive showcase of my ability to blend technical depth with gameplay innovation.
Tell me what you're building and what the constraint is. I take on new builds, rescues of existing projects, and short engagements to work out why something runs badly.
Hire me directly through Upwork, where my full work history and client reviews are public.
Hire me on UpworkBased in the United States. Available for contract work.