Rafael Zuniga | Senior Mobile, Real-Time 3D & SaaS Engineer

If it doesn't feel right on a phone, it doesn't ship.

8+ years specializing in the mobile industry: performance optimization, KPI-driven development, ad systems and mediation, A/B/C testing, and the countless technicalities of getting an app through Google Play and the App Store. A majority of the games in the portfolio below were built cross-platform, designed and developed for both Android and iOS, and shipped by me independently.

If your app's mechanics work but it still doesn't feel right, that's the problem I solve. I've rebuilt native iOS and Android UI/UX top to bottom, turned clunky experiences into ones that finally clicked, and reworked the interface, auth, and backend of an anatomy and pathology app that now serves 35,000 monthly users.

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 stores

15+Apps shipped and serviced on Android/iOS

1M+Downloads on apps I worked on

70k+MAU across apps I've worked on

About Me

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, one line at a time, which is exactly why AI has become such a force multiplier for me: that foundation lets me steer its output with real judgment, rather than just accept what it gives me. I adopted it early, using it to move faster on the parts that don't need my full attention while staying closely involved where it matters. I've also shipped AI-native products, not just used AI to write code.

Tech Stack

Unity / URP C# Shader Programming HLSL / GLSL Compute Shaders Three.js WebGL Real-Time Rendering Performance Profiling Physics & Simulation Procedural Animation Mobile (iOS / Android) UI / UX Engineering Azure & PlayFab Python

What I Actually Do

Three surfaces, one standard: it ships, it's fast, and it holds up with real users.

Native Mobile & UI/UX Engineering

Native iOS and Android, plus Unity on mobile, with the interaction design done from the engineering side
Rebuilding apps that already have users: interaction model, flows, screens, and performance, without breaking what works
Store releases, staged rollouts, analytics and attribution, crash triage, live operations
SDK integration that stays maintainable: auth, payments, ads mediation, push, multiplayer

Real-Time 3D, Shaders & Performance

Custom shaders: cel shading, water, compute-based volumetric fog
Performance engineering: draw-call and triangle budgets, 60+ FPS on modest hardware
Multiplayer and physics that survive network sync; live data driving a real-time scene
Tooling for other developers: animation baking, motion matching, editor workflows

Full-Stack SaaS & Cloud

Multi-tenant architecture, authentication and authorisation, backend APIs
Retrieval and vector search, scheduled ingestion, review and approval workflows
Azure Functions, PlayFab, Firebase, and the deployment pipeline that keeps it running
Products taken from zero to production by one engineer, end to end

AI-Native Engineering

LLM features shipped in production, grounded in real data instead of hallucinated
Semantic search with tenant isolation; evaluation and review loops around model output
AI-assisted delivery with senior review: weeks instead of quarters, without the mess
Finishing what AI prototyping tools started: real auth, real backend, real performance

Shipped Products I Work On

Handling technical publishing, updates, live ops, and maintenance on Google Play & App Store

Anatomist

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.

Mobile Education Unity

Off-Road Champion

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.

Mobile Racing 3D

Polygon Mayhem

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.

Mobile Puzzle UI/UX

My Portfolio

Projects I've built from the ground up across mobile, multiplayer, and casual gaming

Bumper Aliens

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.

Mobile Unity 2D

Space Box

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.

Multiplayer Photon Mobile

Foka GO

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.

Arcade Mobile

Word Wall

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!

Puzzle Casual

Dominoes

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.

Strategy AI

Bubble Shooter

A vibrant bubble shooter game where players aim, match, and pop bubbles to clear levels. With intuitive controls and satisfying mechanics.

Casual Puzzle

3D Runner

A 3D runner with a quadruped character racing through an infinite, curved world. Featuring procedural levels and enemies resulting in a fast-paced challenge.

3D Procedural

Wormhole Madness

A challenging space puzzle game set in a dynamic, ring-filled environment where fuel management and precise navigation are essential for success.

Physics Puzzle

Marshmallow Bounce

A lively arcade game where players launch and bounce their character across a whimsical candy themed landscape. Fun, fast-paced, and endlessly entertaining.

Arcade Casual

Fly Simulation

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.

3D Python UDP Simulation

Spell Blast

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.

Mobile LibGDX 2.5D Action

Dark storybook mystery/horror game (Unity 6 / URP)

My current passion project: a moody, atmospheric night-time exploration game.

🎨 Visual style. A custom cel shader gives the game its dark storybook look: hard, tinted shadow bands, rim light and ink outlines.
💧 Water & volumetric fog. Custom water shaders with Gerstner waves, ripples and flowing rivers. A compute-based volumetric fog drifts with the wind.
🌲 Connected world. A data-driven zone system links areas (forest, river, castle, cave) through exits. Each zone defines its own fog, lighting and post-processing, and gameplay systems hook into transition events.
✨ GPU mesh morphing. 80,000 compute-shader particles flow from one model into the next, then dissolve into the solid mesh.
🎮 Character & camera. Custom motion matching controller with a bake tool for humanoid rigs, plus a camera that switches between first-person, third-person and cinematic views.

My playground for the latest Unity technology, new systems and shaders, and unfiltered creativity.

Selected Technical Work

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.

MORPG Prototype

This 8-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.

Mobile UI/UX & Unity 2D/3D Engineer