Julien is available for hire
Hire JulienJulien Olivier
Verified Expert in Engineering
Software Architect and Developer
Sainte Adèle, Canada
Toptal member since September 22, 2026
Bio
Julien is a senior software architect with 30 years of experience, specializing in web browser internals, GPU rendering engines, and deep-tech systems for clients like Ubisoft, Poietis, and Sunna Design. He has refactored a 1.8-million-line WebKit codebase at Ubisoft to improve memory efficiency. As an inventor with 20+ multi-touch patents, Julien possesses elite C++ expertise, ranging from custom operating system and compiler creation to synthesizing custom CPU/GPU silicon on an FPGA.
Portfolio
Ubisoft
WebKit, Skia, WebCore, JavaScriptCore, OpenSSL, FreeType, Claude Code...
Poietis
NVIDIA CUDA, 3D Graphics Engines, OpenGL, C++, Qt 5, Algorithms...
Moon (Formerly SunnaDesign)
C++, Node.js, Java, NoSQL, Android, Cordova, Firmware Development, JavaScript...
Experience
- Software System Architecture Development - 20 years
- Algorithms - 20 years
- Computer Systems Architecture - 20 years
- Optimization - 20 years
- C++ - 20 years
- Game Programming - 10 years
- WebKit - 8 years
- NVIDIA CUDA - 3 years
Preferred Environment
Git, Visual Studio, Claude
The most amazing...
...codebase I've refactored is a 1.8-million-line WebKit browser engine, reducing memory usage by 30% and loading time by 50% while improving stability.
Work Experience
Senior Software Developer | Engine Programmer
2022 - PRESENT
Ubisoft
- Refactored a 1.8-million-line WebKit codebase to maximize game console memory efficiency, reducing the engine's memory footprint by 30% and accelerating page loading velocity by 50%.
- Designed a custom fast memory allocator for restrictive mono-process environments, entirely mitigating memory leaks during dynamic module reloads across major 10+ AAA games.
- Engineered an optimized platform-specific browser port layer deployed across Xbox Series X/S, PlayStation 4/5, and Nintendo Switch to handle low-latency interactive web rendering.
- Implemented advanced CSS backdrop and filter effect rendering loops by building a custom graphics stack utilizing parallel CPU rendering architectures.
- Integrated automated AI-assisted code review pipelines into GitLab CI/CD alongside GoogleTest, increasing delivered API quality and code test coverage.
Technologies: WebKit, Skia, WebCore, JavaScriptCore, OpenSSL, FreeType, Claude Code, CPU Rendering, 3D Graphics Engines, C++, CMake, Sharpmake, PlayStation, Xbox, Nintendo Switch, MacOS, Steam, PC, Memory Leaks, Memory Pools, Debugging, GitLab CI/CD, Assembly, Jira, Confluence, Visual Studio, Git, JavaScript, HTML5, CSS3, Code Review, Code Refactoring, Xcode, cURL, NVIDIA CUDA, CUDA Kernel, Artificial Intelligence (AI), AI Integration, AI Model Integration, Linux, C, TypeScript, SQL, Cuda, ARM, x64 Assembly, OpenCL, SQLite, Computer Systems Architecture, Programming, Computational Mathematics, Algorithms, GLSG Shaders, TCP/IP, Nintendo, APIs, Gaming Platforms, Optimization, Porting, Reverse Engineering, Makefile, Windows, Platforms, User Interface (UI), Chrome, Game Programming, Game Engine Programming, Concurrent Programming, WebSockets, WebAssembly (Wasm), HTTP, Software System Architecture Development, Computer Graphics, Real-time Rendering Engines, Low-level Programming, Assembly Language, Computer Architecture, High-performance Computing (HPC), R&D, Multithreading, Graphics, Graphics Processing Unit (GPU), Claude, WebGL, Web Standards, Open Source, WebGPU, Vulkan, Browsers, HDR Photography, AI-assisted Development, API Development, Vanilla JS, Stress Testing, Technical Leadership, Real-time Systems, Documentation, Pipelines, Videos, Mobile
Senior Software Developer
2021 - 2022
Poietis
- Designed a high-speed parallel slicing algorithm using NVIDIA CUDA, generating millions of 2D slices per second with multiple infill strategies for laser tissue-printing.
- Transformed a legacy 2.5D tissue-printing program into a full 3D real-time editing software platform, facilitating native support for degenerate, unclosed STEP and OBJ imports.
- Engineered real-time 3D Boolean geometric operations and live mesh optimization algorithms to allow instant interactive object modifications.
Technologies: NVIDIA CUDA, 3D Graphics Engines, OpenGL, C++, Qt 5, Algorithms, Mesh Optimization, GLSG Shaders, JavaScript, Git, Visual Studio, GitHub, Qt 4, User Interface (UI), Design, Code Refactoring, Code Review, Xcode, WebKit, GPU Computing, Linux, SQL, Assembly, Cuda, x64 Assembly, OpenCL, MySQL, SQLite, Programming, Computational Mathematics, MacOS, PC, Memory Leaks, Memory Pools, Debugging, Full-stack, Optimization, Porting, Makefile, Windows, Platforms, CUDA Kernel, Computer Graphics, Low-level Programming, High-performance Computing (HPC), R&D, Multithreading, Graphics, Graphics Processing Unit (GPU), Doxygen, WebGL, Vanilla JS, Real-time Systems, Documentation
Chief Software Officer
2017 - 2021
Moon (Formerly SunnaDesign)
- Scaled a high-performance C++/Node.js graph database instance to sustain 20,000 concurrent connections per instance and process millions of operational records per hour.
- Designed a secure, bidirectional SMS data communication channel on Android devices, ensuring 100% critical data connectivity in remote areas lacking internet infrastructure.
- Developed custom Android 6-10 firmware modules and specialized IoT pay-as-you-go (PAYG) software systems to manage hardware activation and power allocation algorithms.
- Integrated Orange Money and Tigo Cash payment APIs, simplifying complex field sales workflows and de-risking financial collection systems in deep rural areas.
- Formulated full-stack operational tools incorporating geolocation, scoring, and inventory management to scale technical execution across Senegal.
Technologies: C++, Node.js, Java, NoSQL, Android, Cordova, Firmware Development, JavaScript, HTML5, CSS3, Solar, Energy Storage, Lighting, Geolocation, CRM, Fleet Management, Sourcing, SMS Gateways, Payment APIs, Visual Studio, Code Review, C, SQL, Assembly, ARM, x64 Assembly, React, React Native, PostgreSQL, MySQL, SQLite, MongoDB, Couchbase, Lightning Memory-Mapped Database (LMDB), Graph Databases, Electronics, Integrated Circuits, Computer Systems Architecture, Programming, PC, Memory Leaks, Memory Pools, Debugging, Algorithms, Bluetooth, Business Models, Business Planning, Investor Presentations, IT Manufacturing, Full-stack, TCP/IP, 3D Design, SOLIDWORKS, STM32, Optimization, Porting, Platforms, User Interface (UI), Design, WebSockets, Data Processing, Cross-functional Communication, System Architecture Design, Software System Architecture Development, Real-time Embedded Systems, Low-level Programming, Multithreading, Puppeteer, Jest, Doxygen, Web Standards, Browsers, Vanilla JS, Stress Testing, Technical Leadership, Documentation, Mobile
CTO Director of Technology
2016 - 2017
Sunna Design
- Directed end-to-end software development for connected solar-powered public lighting, managing technology strategy, engineering talent acquisition, and scaling.
- Developed SunnaCloud, a full-stack IoT platform optimized for real-time remote product management, power-usage monitoring, and telemetry logging.
- Built SunnApp, a custom Bluetooth low-energy Android application enabling reliable offline field data collection and hardware activation in low-connectivity zones.
- Conceived the foundational PAYG software architecture and business model used to distribute and loan solar power products across West Africa.
Technologies: Android, iOS, Java, C++, JavaScript, HTML, CSS, Node.js, Neo4j, Lighting, Energy Storage, Solar, Bluetooth, Business Models, Business Planning, NoSQL, Firmware Development, Sourcing, Electronics, Investor Presentations, WebView, C, SQL, Assembly, ARM, x64 Assembly, React, React Native, PostgreSQL, MySQL, SQLite, MongoDB, Couchbase, Lightning Memory-Mapped Database (LMDB), Graph Databases, Integrated Circuits, Computer Systems Architecture, Programming, PC, Memory Leaks, Memory Pools, Debugging, Algorithms, Cordova, Geolocation, CRM, Fleet Management, IT Manufacturing, Full-stack, TCP/IP, 3D Design, SOLIDWORKS, STM32, Optimization, Porting, Platforms, User Interface (UI), Design, Code Review, Chrome, WebSockets, Cross-functional Communication, System Architecture Design, Software System Architecture Development, Computer Graphics, Real-time Embedded Systems, Low-level Programming, R&D, Multithreading, Puppeteer, Jest, Doxygen, Web Standards, Browsers, Vanilla JS, Stress Testing, Technical Leadership, Documentation, Mobile
Co-founder and Chief Software/Hardware Architect
2005 - 2015
Stantum (Formerly JazzMutant)
- Built a high-speed HTML5/CSS3 custom web browser engine from scratch, featuring native OpenGL and DirectX GPU acceleration, optimized for low-memory ARM tablets.
- Converted proprietary FPGA multi-touch controllers into production-ready commercial ASIC silicon architectures, including STM32, Sitronix, and TSMC platforms.
- Ported custom multitouch software APIs natively to Linux, Android, and iOS, expanding the company's addressable commercial hardware platform reach.
- Architected and developed the full-stack Galago education tablet platform using a scalable JavaScript, Node.js, and NoSQL database ecosystem deployed across French national schools.
- Engineered custom Android tablet firmware modules for the Galago national education project, enabling centralized, secure device and network profile management.
- Created a high-performance graph database solution with automated dynamic network synchronization and granular access-rights management using PHP, C++, and JavaScript.
Technologies: FPGA, ASIC, Linux, Android, iOS, HTML5, CSS3, OpenGL, DirectX, WebView, Chromium Embedded Framework (CEF), Electronics, Multi-touch Attribution, Integrated Circuits, Business Models, Business Planning, Investor Presentations, IT Manufacturing, Sourcing, C++, JavaScript, Full-stack, Node.js, Firmware Development, TCP/IP, Patent Applications, Visual Studio, Code Review, MacOS, Xcode, WebKit, Chrome, GPU Computing, FreeType, C, SQL, Assembly, ARM, x64 Assembly, React, React Native, MySQL, SQLite, Lightning Memory-Mapped Database (LMDB), Graph Databases, Computer Systems Architecture, Programming, Physics, Computational Mathematics, CPU Rendering, 3D Graphics Engines, CMake, PC, Memory Leaks, Memory Pools, Debugging, Algorithms, Cordova, CRM, 3D Design, SOLIDWORKS, Altera Quartus, Xilinx Ise, Xilinx Spartan, STM32, APIs, Simulators, Optimization, Porting, Reverse Engineering, Windows, Platforms, User Interface (UI), Design, Code Refactoring, Subversion (SVN), Concurrent Programming, WebSockets, HTTP, Data Processing, System Architecture, Cross-functional Communication, System Architecture Design, Software System Architecture Development, Computer Graphics, Real-time Rendering Engines, Real-time Embedded Systems, Low-level Programming, Kernel Programming, Real-time Operating System (RTOS), Compiler Design, Assembly Language, VHDL, Verilog HDL, Computer Architecture, R&D, Intellectual Property, Multithreading, Graphics, Graphics Processing Unit (GPU), Doxygen, Web Standards, Open Source, Browsers, HDR Photography, API Development, Vanilla JS, Stress Testing, Technical Leadership, Real-time Systems, Documentation, Videos, Mobile
Co-founder & Software/Hardware Architect
2002 - 2005
JazzMutant
- Authored 24+ foundational commercial patents for advanced multi-touch panel sensing and hardware-processing technologies heavily utilized in modern consumer devices.
- Co-created the Lemur, the industry's first 10-touch tactile tablet for real-time music and lighting control using advanced OSC and MIDI communication protocols.
- Engineered an Altera Stratix FPGA-based embedded computer layout, including proprietary operating system kernels, GUI window tooling, and custom 2D/3D GPU and FPU hardware IP cores.
- Developed low-level processing algorithms, custom board mechanics, integrated circuit paths, and a zero-loss network stack for multi-device synchronization.
Technologies: OSC, MIDI, C++, JavaScript, HTML5, CSS3, DirectX, OpenGL, Multi-touch Attribution, Electronics, Integrated Circuits, FPGA, Sourcing, 3D Design, SOLIDWORKS, ProTools, Assembly, Altera Quartus, Xilinx Ise, Xilinx Spartan, STM32, Business Planning, Investor Presentations, Patent Applications, Visual Studio, Subversion (SVN), Xcode, Git, PHP, FreeType, Linux, C, SQL, ARM, x64 Assembly, MySQL, SQLite, Computer Systems Architecture, Programming, Physics, Computational Mathematics, CPU Rendering, 3D Graphics Engines, MacOS, PC, Memory Leaks, Memory Pools, Debugging, Algorithms, Firmware Development, CRM, IT Manufacturing, Full-stack, TCP/IP, Audio Codecs, APIs, FFTW, Simulators, Optimization, Porting, Reverse Engineering, Windows, Platforms, User Interface (UI), Design, Code Refactoring, Carbon, Concurrent Programming, HTTP, System Architecture, Cross-functional Communication, System Architecture Design, Software System Architecture Development, Computer Graphics, Real-time Rendering Engines, Real-time Embedded Systems, Low-level Programming, Kernel Programming, Real-time Operating System (RTOS), Compiler Design, Assembly Language, VHDL, Verilog HDL, Computer Architecture, High-performance Computing (HPC), R&D, Intellectual Property, Multithreading, Graphics, Graphics Processing Unit (GPU), Doxygen, Web Standards, Open Source, API Development, Vanilla JS, Stress Testing, Technical Leadership, Real-time Systems, Documentation, Videos
Founder & Software/Hardware Developer
1999 - 2002
Skaven Software
- Developed a proprietary multiplayer game engine capable of supporting 4,000+ simultaneous concurrent players using optimized low-level UDP networking.
- Developed and commercialized a custom PlayStation API emulator and multi-platform devkit with integrated, in-IDE remote debugging and DirectX rendering.
- Conceived wavelet-based and lossless video compression codecs that significantly outperformed DivX velocities and efficiency for data archive storage systems.
- Designed StarSync PP1, an embedded real-time player and recorder utilizing FFmpeg, MIDI, and SMPTE clock sync running on a custom x86 embedded operating system.
- Served as a lead engine developer for Deibus ATV Mania on PlayStation, implementing custom real-time 3D collision physics, AI pipelines, and interface architectures.
Technologies: FFmpeg, C++, DirectX, OpenGL, PlayStation, Nintendo, GameBoy Advance, Video Compression, Audio Codecs, MacOS, PC, Linux, APIs, Gaming Platforms, Wavelets, FFTW, Electronics, Firmware Development, Simulators, 3D Graphics Engines, 3D Design, SOLIDWORKS, Military, Investor Presentations, Visual Studio, Subversion (SVN), Visual SourceSafe, CodeWarrior, Carbon, Artificial Intelligence (AI), Game Physics, Game Programming, Game Engine Programming, C, SQL, Assembly, ARM, x64 Assembly, MySQL, SQLite, Integrated Circuits, Computer Systems Architecture, Programming, Physics, Computational Mathematics, CPU Rendering, Memory Leaks, Memory Pools, Debugging, Algorithms, Mesh Optimization, CRM, Full-stack, TCP/IP, Altera Quartus, Optimization, Porting, Reverse Engineering, PHP, Windows, Platforms, User Interface (UI), Code Refactoring, Concurrent Programming, HTTP, System Architecture, System Architecture Design, Software System Architecture Development, Computer Graphics, Real-time Rendering Engines, Real-time Embedded Systems, Low-level Programming, Kernel Programming, Real-time Operating System (RTOS), Compiler Design, Assembly Language, Computer Architecture, High-performance Computing (HPC), R&D, Multithreading, Graphics, Graphics Processing Unit (GPU), Web Standards, HDR Photography, API Development, Stress Testing, Real-time Systems, Documentation, Videos
Game Developer | Lead Developer, R&D
1997 - 1999
Cryo Interactive
- Reengineered the legacy DOS title Deo Gratias into a modern DirectX port with a brand-new graphics engine, completing full deployment to production inside 6 months.
- Optimized a high-performance 2D graphics rendering engine to achieve native support for Voodoo 3dfx and Intel MMX chipsets via DirectX interfaces.
- Built parallel video and audio asset compression tools designed to scale across hundreds of local machines, significantly accelerating team R&D throughput.
- Developed core system engines, dynamic ambient music systems, and specialized interface graphics scripts for major distributed titles like Black Moon Chronicles.
Technologies: DirectSound, DirectX, Assembly, C++, Visual SourceSafe, Visual Studio, Video Compression, 3D Graphics Engines, Game Physics, Optimization, Debugging, Porting, PlayStation, PC, Reverse Engineering, Algorithms, C, PHP, CodeWarrior, Artificial Intelligence (AI), Game Programming, Game Engine Programming, Computer Systems Architecture, Programming, Physics, Computational Mathematics, CPU Rendering, Memory Leaks, Memory Pools, Mesh Optimization, TCP/IP, Audio Codecs, APIs, Gaming Platforms, FFTW, Simulators, Windows, Platforms, User Interface (UI), Code Refactoring, Concurrent Programming, HTTP, Computer Graphics, Real-time Rendering Engines, Low-level Programming, Assembly Language, Computer Architecture, High-performance Computing (HPC), R&D, Multithreading, Graphics, Graphics Processing Unit (GPU), API Development, Stress Testing, Real-time Systems, Documentation, Videos
Experience
QuickJS-PAL
http://github.com/j-olivier/quickjs-palDeveloped a QuickJS fork featuring a platform abstraction layer to streamline development and porting across multiple devices and game consoles. This fork includes support for Visual Studio, LLVM, and CLang, and replaces fatal abort() calls with an uncatchable JavaScript Exception.
TradeView
A high-performance, web-based trading intelligence platform built for seamless big-data exploration and algorithm development. Engineered with a highly intuitive graphical interface, it enables traders to navigate massive historical stock datasets down to the millisecond tick.
By leveraging CUDA and WebAssembly (WASM) hardware acceleration, TradeView delivers lightning-fast processing power directly to your browser. The platform features an advanced TensorFlow-powered AI engine to execute high-dimensional statistical analysis, alongside a native JavaScript environment for backtesting complex trading algorithms in real time. Powered by a custom local server, TradeView connects directly to the Interactive Brokers (IBKR) API for reliable, real-time database access and execution.
By leveraging CUDA and WebAssembly (WASM) hardware acceleration, TradeView delivers lightning-fast processing power directly to your browser. The platform features an advanced TensorFlow-powered AI engine to execute high-dimensional statistical analysis, alongside a native JavaScript environment for backtesting complex trading algorithms in real time. Powered by a custom local server, TradeView connects directly to the Interactive Brokers (IBKR) API for reliable, real-time database access and execution.
Education
1996 - 1998
Bachelor's Degree in Electronic and Industrial Computing
Cachan University Institute of Technology - Cachan, France
Skills
Libraries/APIs
Skia, Node.js, OpenGL, DirectX, FFmpeg, React, FFTW, WebGL, WebGPU, Vulkan, OpenSSL, Puppeteer, Carbon, Interactive Brokers API, TensorFlow, API Development
Tools
Visual Studio, WebView, DirectSound, Git, Claude, Claude Code, SOLIDWORKS, Altera Quartus, CMake, Sharpmake, GitLab CI/CD, Jira, Confluence, ProTools, Xilinx Ise, Visual SourceSafe, Makefile, MinGW, GitHub, Xcode, Subversion (SVN), CodeWarrior
Languages
C++, JavaScript, HTML, CSS, HTML5, CSS3, C, Assembly, x64 Assembly, Assembly Language, PHP, VHDL, Verilog HDL, Java, TypeScript, SQL
Frameworks
Vanilla JS, JavaScriptCore, Chromium Embedded Framework (CEF), OpenCL, React Native, Qt 5, Chrome, Jest
Paradigms
Code Refactoring, Concurrent Programming, High-performance Computing (HPC), Stress Testing, Real-time Systems, Compiler Design, Wavelets
Platforms
Android, PlayStation, PC, Windows, Kernel Programming, NVIDIA CUDA, Linux, Xbox, MacOS, Mobile, iOS, Steam, STM32
Storage
WebCore, MySQL, SQLite, Graph Databases, NoSQL, Neo4j, PostgreSQL, MongoDB, Couchbase
Other
WebKit, GPU Computing, FreeType, FPGA, OSC, ARM, Lightning Memory-Mapped Database (LMDB), Electronics, Integrated Circuits, Computer Systems Architecture, Programming, Computational Mathematics, CPU Rendering, 3D Graphics Engines, Memory Leaks, Memory Pools, Debugging, Algorithms, Mesh Optimization, Firmware Development, Multi-touch Attribution, Full-stack, TCP/IP, Video Compression, APIs, Gaming Platforms, Game Physics, Optimization, Porting, Reverse Engineering, Platforms, User Interface (UI), Game Programming, Game Engine Programming, WebSockets, HTTP, System Architecture, System Architecture Design, Software System Architecture Development, Computer Graphics, Real-time Rendering Engines, Real-time Embedded Systems, Low-level Programming, Real-time Operating System (RTOS), Computer Architecture, R&D, Multithreading, Graphics, Graphics Processing Unit (GPU), Web Standards, Open Source, Browsers, HDR Photography, Technical Leadership, Documentation, Videos, ASIC, MIDI, Cuda, Physics, GLSG Shaders, Cordova, Solar, Energy Storage, Lighting, Geolocation, CRM, Fleet Management, Sourcing, Bluetooth, Investor Presentations, IT Manufacturing, 3D Design, Nintendo, GameBoy Advance, Audio Codecs, Simulators, Qt 4, Design, Code Review, cURL, CUDA Kernel, Artificial Intelligence (AI), WebAssembly (Wasm), Data Processing, Cross-functional Communication, Intellectual Property, AI-assisted Development, Pipelines, Doxygen, Nintendo Switch, SMS Gateways, Payment APIs, Business Models, Business Planning, Xilinx Spartan, Patent Applications, Military, AI Integration, AI Model Integration
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