01
Engine audio authoring
C++ audio simulation, native and WebAssembly runtimes, browser studio, and an LLM feedback loop for authoring and evaluating responsive engine audio.
Open- C++
- WASM
- Web Audio
- LLM agents
- React
- TypeScript
- AWS
Svetlozar Valchev
Principal product & systems engineer.
I build AI-enabled products where agents have to operate real software: engines, simulations, runtimes, browser tools, and production infrastructure. I work across the system underneath the model, the product around it, and the path into production.
engagements: contract / fractional principal engineer
- 01LLM / agentic tooling
- 02C++ / runtimes
- 03real-time / simulation
- 04TypeScript / product
- 05AWS / delivery
~/work
Selected engineering work.
Organised by the system I worked on, not by job title. Spanning game engines, agentic tooling, simulation, healthcare, media, payments, mobile, and the web.
02
Cross-platform game engine
Rendering, scripting, UI, asset pipelines, multiplayer systems, developer tooling, and native authenticated MCP access for AI agents.
Open- C++
- CMake
- V8
- TypeScript
- MCP
- Vulkan / Metal
03
AI product integrations
Product integrations for LoRA-based ecommerce generation, a Unity text/image-to-3D and texturing plugin, Unreal integration, and custom terrain-model workflows.
- Python
- TensorFlow
- LoRA
- Text-to-3D
- Unity
- Unreal Engine 5
- React
- Azure
04
Media generation pipeline
Visual template editing and a server-side Canvas/FFmpeg rendering pipeline for personalised digital athlete cards.
- React
- Node.js
- AWS Lambda
- S3
- Canvas
- FFmpeg
- Three.js
05
Mobile social platform
Built a React Native social discovery app and its Laravel backend, including real-time synchronisation, offline-first flows, Firebase integration, and a documented, tested API.
- React Native
- Laravel
- MySQL
- Firebase
06
Mobile game systems
A mobile dress-up game built first in React Native and later transitioned to Unity, with a shared backend and content tools for assets, recipes, blueprints, shopping, and analytics.
- Unity
- React Native
- Vue
- Node.js
- PostgreSQL
- Firebase
07
Multiplayer gameplay systems
Client/server combat, inventory, abilities, match state, NPCs, and replicated interactions for a survival game supporting up to 24 players.
- Core / Manticore
- Lua
- Multiplayer
- Game systems
08
Clinical product systems
FHIR clinical systems spanning care planning, medication and therapy workflows, patient monitoring, device data, and interactive 3D body mapping.
- Vue
- Three.js
- Node.js
- FHIR
- WebGL
09
Constrained-device UI
High-performance television interfaces, a memory-conscious custom MVVM framework, and a multi-client white-label platform.
- JavaScript
- WebSocket
- Custom MVVM
- Embedded web
10
Vehicle simulator UI
Angular.js architecture and core interface systems for the vehicle simulator's modernised frontend.
- Angular.js
- Lua
- Game UI
11
Insurance integration
Policy-management and mobile claims systems with an integration layer connecting multiple insurance providers.
- Aurelia
- Node.js
- MongoDB
- Integrations
12
HTML5 game engine
Casino game platform, a custom engine tuned for mobile devices, and its cross-platform animation system.
- JavaScript
- HTML5 Canvas
- CSS
- Game engine
13
Payment infrastructure
Payment gateway supporting more than 20 providers, plus internal analytics and customer support systems.
- PHP
- MySQL
- JavaScript
- Payments
14
Web platforms
Real-estate platforms, auction systems, educational tools, and browser-based 3D charting.
- PHP
- JavaScript
- MySQL
- 3D web
15
Browser RPG
Designed, built, and operated a web role-playing game that reached more than 10,000 active players.
- PHP
- MySQL
- JavaScript
- Operations
~/services
Where I can help.
Products that combine AI with difficult systems need senior judgment and hands-on execution, not another layer of coordination.
01
Principal / founding engineer
For founders and engineering teams building products where architecture, implementation, and delivery need the same senior owner.
- Technical direction
- Hands-on implementation
- Production ownership
02
Technical rescue and productionisation
For stalled prototypes, risky architecture, performance problems, and difficult transitions into production.
- System diagnosis
- Critical-path prototype
- Concrete delivery plan
Good fit: agentic developer tools, simulation, real-time systems, complex B2B software, and commercial products built around C++ or browser runtimes.
Contact~/experience
Two decades in production.
The technologies changed. The job stayed consistent: understand the real constraint, build the critical path, and carry it into production.
Full CV- 2025 - now
SPARQ game engine
Co-founder building a cross-platform C++ engine across rendering, runtimes, tooling, multiplayer systems, and cloud delivery.
- 2019 - 2024
Healthcare and product platforms
Patient monitoring, 3D visualization, device integration, and full-stack product systems.
- 2015 - 2019
Performance-constrained interfaces
BeamNG.drive UI foundations and high-performance television interfaces for low-end hardware.
- 2006 - 2015
Web products, games, and infrastructure
From a 10,000+ player web RPG to payment systems, analytics, insurance, and HTML5 game engines.
~/contact
Start with the context.
Write it down or talk it through. Describe what you are building, where it is stuck, and what needs to happen next. I will be direct about whether I am the right fit.
project fit call30 minutes
Talk it through.
Use the call to clarify the problem and identify a practical next step.
- The product and its current state
- The technical risk or blocker
- The next milestone and timing