David Erik García Arenas
Software Engineer · C++ · Python · graphics, simulation, developer tools & 3D pipelines
I build software and tools that help teams test and fix complex graphics and simulation systems.
help.Click a question or type your own. It's a real shell too: try ls, cd projects, cmd or help.
HighlightsStart
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- Work permitEU citizen, none needed
- LanguagesSpanish · English C1
Research prototype, not playable. 99.73% of its pixel shaders translate cleanly.
01 · SELECTED WORK01 · SELECT A STAGEProjects
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Sonic 4: Episode II
Rebuilding a 2012 Sonic game in modern C++, checked against the original.
C++17 reconstruction of the 2012 PC release: matching behaviour, not bytes. Selected routines checked against the original code with zero recorded differences.
02 · CAREERExperience & education
Full history →3D Pipeline Validation & Tooling · Paradox Cat GmbH
- Sole author of the team's pre-delivery validation framework for BMW automotive 3D data: one core serving a Qt/QML desktop app, a web dashboard and a CLI.
- Native layer in C++/CMake against the Ramses rendering SDK; the Python core validates its report before recording evidence.
- Around 1,800 automated tests across 21 surfaces, run against 26 real car models.
Test Automation Engineer · Paradox Cat GmbH
- Validated Android Automotive HMI with ADB, dumpsys and runtime diagnostics on embedded and bench systems.
- Built Maestro flows, then created QUANTUM Inspector in Python and Qt.
BSc (Hons) Computer Science (Top-Up)
Técnico Superior, Desarrollo de Aplicaciones Web (DAW)
Técnico Superior, Desarrollo de Aplicaciones Multiplataforma (DAM)
Técnico, Microcomputer Systems & Networks
03 · LATEST POSTSBlog
All posts →- Yes, x87. In 2026.A 2012 game's maths gives slightly different answers on a modern 64-bit build. Why that happens, and how I made both builds agree.Write-up
- Alpha to coverage, hands-onA demo you can play with in the browser: three ways a graphics card can draw see-through hair, side by side.Demo
- The swapchain hazard my GPU forgaveA timing bug in how my renderer hands finished frames to the screen. My graphics card tolerated it; a checking tool caught it.Write-up
04 · ABOUTAbout me
Why I do this
I started in testing, asking why a test fails and whether I can trust what it reports. That led to diagnostics, then to validating 3D pipelines, and now to building runtime, simulation and graphics software. In my spare time I rebuild games, because making something behave exactly like the original is the hardest test of understanding it. Long term, I want to make games.
Certifications & languages
- C1 Advanced (CAE) · Cambridge English
- Foundations of Software Testing and Validation · University of Leeds
- Agile with Atlassian Jira · Atlassian
Spanish (native) · English (C1) · German and French (learning)
Prefer it as a terminal? Type neofetch up top.
What colleagues say
Erik quickly demonstrated a strong sense of ownership, curiosity and professionalism. Despite being an intern, he consistently approached tasks with the mindset of a full team member, taking responsibility for his work and striving to deliver high-quality results.
David is the kind of engineer who quickly moves from learning a system to finding ways to improve it. … I watched him grow into an increasingly independent engineer who consistently went beyond what I would normally expect from an intern.
05 · OPTIONAL05 · INSERT COINExtrasGo deeper
optional · same facts, more funWhy these exist: the rest of this page is the CV; these are the playground. Each one is the same portfolio behind a different front end, and each is real engineering: HawaiiOS is a Windows-style desktop I wrote in TypeScript and Three.js, and Work Adventure is a console-style game menu in C++, compiled to WebAssembly. Rendering, input, state and performance, just with more fun. Work Adventure builds on the UI work of the UnleashedRecomp project.
Boot the full desktop
Real windows, live tiles and a WebGL street, all in the browser.
INSERT COINPlay my fork
My fork of the open-source fan game NSMB Mario vs Luigi, with a free-roam hub I added. Used with its developers' permission.
TRY ITAlpha to coverage
Blend, test or coverage, live in WebGL2.
Get in touch
Email is the quickest way to reach me: daviderikgarciaarenas@gmail.com. Based in Munich, Germany; I work in English and Spanish.