Hire the Best C# Developers & Programmers
in Japan

Hi I’m Christian and I’m a professional game developer with over 10 years of experience. I have worked on both client and server side, and have developed many types of multiplatform games, including VR and AR games. For me user experience is very important, so rest assured I will deliver you intuitive and easy to use optimized games. Here is what I can offer to you: ➡️ Game Development: - Over 10 years of experience ( 10,000+ hours on Upwork ) developing games. - Client & Server side development experience. - Great communication skills. Recently I have worked as development team leader, twice. - Plenty of experience using Git. - Use of Software Architecture patterns for a high quality and easy to mantain game. - UX design skills to adjust the application to different screen resolutions. ➡️ Unity 3D - More than 10 years of experience making games and apps using Unity and C# - High quality code for an optimized and light size game builds. - Strong knowledge in all areas of Unity: Ui, Shaders / Materials, Animation, Unity Backend Services, etc. - Implementation of Addressables for remote assets loading. - Implementation of external APIs ( RESTful API, WebSockets, Firebase, etc. ) - Deployment in multiple platforms Android, IOS, WebGL, Windows, Mac, etc. - Augmented Reality and Virtual Reality development. ➡️ Web Game Development - Plenty of experience in pure Web Game Development - Knowledge in HTML5, CSS, Javascript and libraries like JQuery and Phaser. ➡️ Game Development without Engine - Solid knowledge in C++ - Experience using Dirext X as Graphics API. - HSL Shader development and other effets implementation like Shadow Maps. ➡️ Backend Development and CI/CD - Server setup and backend services development using Java or Node JS. - Database implementation using MySql or MongoDB. - CI/CD for automatic Client and Server builds deployment, making development faster. I'm a very easy to work with developer, who not only understand the requirements of the job but can also suggest improvements or ideas to make your project even more succesful. Looking forward to work with you!

I help clients turn game ideas, prototypes, and existing projects into playable, reliable systems that can be tested, improved, shipped, and maintained. My main focus is Unity game development, including gameplay programming, UI-driven game loops, mobile and WebGL builds, scoring systems, progression, player interactions, content workflows, and production-ready features. I work especially well on projects that need more than code implementation. I can help structure the gameplay flow, identify missing requirements, improve usability, troubleshoot technical issues, and make sure the project remains practical to maintain after delivery. What I can help with: • Gameplay systems, interactions, and core game loops • Playable prototypes, MVPs, and vertical slices • Improving, debugging, or completing existing Unity projects • UI, menus, scoring, timers, progression, feedback, and game flow • Mobile, WebGL, desktop, browser, and Linux builds • Data-driven content using JSON and CSV • Custom tools and workflows for easier content updates • Bug fixing, optimization, project cleanup, and stability improvements • External service, API, and local AI integration • Controller support, device deployment, and hardware troubleshooting Alongside Unity, I have practical experience with Unreal Engine 5, Godot 4, Construct 3, C#, GDScript, JavaScript, Node.js, Rust, Linux, Blender, and Git. My recent independent R&D work includes deploying a Godot game to an ARM64 Linux handheld and building a communication pipeline between a GB Studio ROM, a modified emulator, Node.js, and a local Ollama model. My Upwork history includes shipped mobile games, Unity ports, long-term production work, WebGL builds, prototypes, gameplay systems, and production support across desktop, mobile, and browser platforms. I work best with clients who want a practical developer who can think through both the technical implementation and the game design direction.

💡 Got a game or app idea? I'll build it right, fast, and clean. I'm Isma, a game programmer and developer with 7+ years of experience turning ideas into polished 2D/3D games and interactive apps, built with Unity, Godot, and across web and mobile. What I do: 🎮 Game development (Unity & Godot, 2D & 3D) 📱Mobile apps (Android & iOS) 🌐 Web & desktop applications ⚡ Performance optimization & bug fixing 🚀 Prototyping & MVPs If you want someone who can handle both the creative and technical sides, and deliver polished, reliable results, I'd love to chat!

Hi, I'm Yohan—a former programmer at two Japanese studios, now a full-time indie developer and consultant. I build fun, polished games and prototypes fast, then help you take them all the way to launch. What I can do for you End-to-End Game Development PC, console, Android, iOS Unity (C#), Unreal Engine 5 (C++/Blueprints) & Godot (C#/GDScript) Optimised builds, store-ready packages Multiplayer & Live Ops Photon Fusion / Mirror / PlayFab Unreal Networking & EOS Matchmaking, leaderboards, live events Next-Gen AI-Assisted Development (Optional) Fast Concept Validation – I use AI to quickly prototype and pressure-test ideas, so we know a mechanic is fun before investing in production code. Efficient Feature Scaling – Once I've built a rock-solid architecture, I offload routine feature work to AI to accelerate delivery while keeping review tight. No Blind Automation – I never hand complex debugging or core architecture to AI. Keeping humans in control of the foundations avoids the performance hits and technical debt that AI-generated code often introduces. Game Design & Documentation Original concepts, monetisation hooks GDDs, technical specs, task breakdowns QA & Play-Testing In-depth bug hunts, balance reviews Actionable reports with clear fixes Why clients hire me Pro studio background – shipped hyper-casual mobile titles, VR experiences, and console/PC projects in Japan. Full-stack mindset – code, design, art pipelines, build automation, Web3/NFT integration. Speed with quality – clear milestones, frequent builds, no surprises. Creative partner – I don't just execute; I suggest fresh ideas and better workflows. Let's talk.

With 25+ years building mission-critical trading systems for investment banks, hedge funds, and professional traders, I bring genuine front-office experience to every project - not just technical skills, but a deep understanding of what traders actually need and the low margin for error that comes with it. My background includes roles on the trading floors of ING Barings and UBS Securities, where I developed equity solutions in high-pressure, time-critical environments. Since then I've worked extensively with hedge funds and private investors, most recently in an ongoing relationship with a New York hedge fund spanning 5+ years, building strategy screeners, broker connectivity via Interactive Brokers/QuickFIX, and risk management reporting across Excel, Python, and Azure SQL Database. One of my core specialties is the intersection of Excel and C# - building sophisticated, real-time trading tools using Excel DNA, multithreaded C# DLLs, and custom broker APIs that go well beyond what standard VBA can deliver. I'm equally comfortable at the quant/data layer (Python, Plotly Dash, Bloomberg, Eikon) and the execution layer (QuickFIX, FIX Protocol, broker APIs). I have a particular talent for untangling complex, hard-to-reproduce bugs in live trading environments - the kind of problems that require both deep technical knowledge and genuine market understanding to diagnose. I'm looking for long-term client relationships with serious projects. If you're building something sophisticated in the trading/fintech space, let's talk.

I am a seasoned software engineer, entrepreneur, and product manager with over 20 years of experience in the game and tech industry. My career spans a wide range of roles, from developing engaging games to leading cross-functional teams and defining strategies for successful product launches. I excel at blending technical expertise with business and product management skills to create user-focused, innovative solutions that drive growth and engagement. After spending 10+ years as a software engineer, I transitioned into entrepreneurship and founded a mobile game publishing company in Japan. I played a pivotal role in the end-to-end lifecycle of products, from conception to market success. My responsibilities included: • Product Strategy: Defining product visions, roadmaps, and KPIs to align with market needs and business objectives. • Development Processes: Selecting architecture and backend technologies, and streamlining workflows for efficient development cycles. • Publishing Management: Designing acquisition-to-publishing workflows, incorporating KPI tracking, localization, and cultural adaptation to maximize product appeal. • Budget Planning: Preparing detailed budgets, balancing promotion costs, expected revenues, and labor expenses to optimize ROI. • Team Leadership: Managing a diverse team of 20+ collaborators, including software engineers, game directors, artists, and business developers. Core Skills and Expertise: • Product Management: Proven ability to define, plan, and execute product roadmaps, ensuring alignment with user needs and business goals. • Game Development: End-to-end development of mobile and console games, focusing on engaging user experiences. • Gamification & User Engagement: Designing mechanics, reward system and achievement to increase retention, drive progression, and enhance overall satisfaction. • Backend Architecture: Building scalable and secure systems to support real-time analytics, multiplayer features, and dynamic configurations. • Team Management: Leading multidisciplinary teams, fostering collaboration, and ensuring timely delivery of high-quality products. Notable Achievements: • TinyHoopers: Creator and lead developer of TinyHoopers, a mobile sandbox-style basketball game combining 2D pixel art with 3D environments. The game has grown to include 6K iOS and 6.5K Android beta players, 20K newsletter subscribers, 48.1K Instagram followers, and an 8.5K-member Discord community. I drove the product vision, mechanics design, backend development, and community engagement strategy. • Mobile Game Publishing: Successfully launched multiple mobile games tailored for the Japanese market, achieving sustainable growth through KPI-driven strategies and cultural customization. • Entrepreneurship: Built and managed a successful publishing company, gaining hands-on experience in product lifecycle management and scaling operations. Product Management Strengths: • Market-Driven Strategy: Strong ability to identify market trends, analyze user behavior, and prioritize features that maximize product value. • Roadmap Execution: Proven success in delivering projects on time and within budget by balancing resources, timelines, and objectives. • Data-Driven Decision Making: Extensive experience leveraging KPIs and analytics to inform product direction and optimize performance. • User-Centric Focus: Deep understanding of how to create compelling user experiences that meet the needs of diverse audiences. Why Choose Me: I bring a unique combination of product management expertise, technical skills, and entrepreneurial experience. Whether you need someone to define a product vision, lead a multidisciplinary team, or ensure a successful launch, I have the experience and track record to deliver results.