KEIX Co., Ltd.
We believe that optimized software is built on clarity, precision, and a deep understanding of the systems it runs on. Our philosophy is simple: strong foundations create resilient software. This belief guides us in every project, from the first line of code to long-term maintenance.
Our work spans from bare-metal and operating system design to resilient cloud architectures, always focusing on performance without sacrificing maintainability. We write software to last — code that is transparent, efficient, and free from hidden behavior, because true reliability starts at the lowest level of the system.
Our Expertise
From system-level programming to cloud-native infrastructure, our expertise covers the full spectrum of modern software development. We design custom operating systems for experimental research and industrial use, implement efficient backend services that scale, and optimize applications for performance-critical environments where predictability is key.
Our team is fluent in Zig, C/C++, Rust, Go, and Python, JavaScript and Common Lisp, Haskell or etc... With a deep focus on GNU/Linux and UNIX-inspired design principles. This breadth allows us to bridge low-level programming with high-level architecture, ensuring systems are not only functional but also elegant, maintainable, and robust against change.
Engagements
For collaboration, consulting, or educational engagements, please feel free to get in touch. We welcome inquiries from individuals, organizations, startups, and academic institutions.
We are particularly interested in projects that emphasize technical depth — whether in operating systems, low-level programming, compiler and emulator design, or the architecture of sustainable infrastructure. Our consulting services range from performance tuning of existing systems to designing entirely new platforms that demand stability and long-term clarity.
In addition, we provide educational support for advanced learners in computer science, helping students and professionals deepen their understanding of how systems truly work beneath the surface. This includes creating detailed technical documentation, offering workshops, and guiding learners through the complexities of operating systems and kernel-level development.
Technical Notes
This site is built in Go and runs as a single, self-contained binary. Go’s speed, reliability, and simplicity make it an ideal choice for delivering a fast and lightweight experience.
We believe in using the right tool for the right job — while Zig and C may be ideal for kernel-level work, Go shines in its ability to produce clean, minimal binaries for web and infrastructure services. By combining these technologies, we demonstrate our core principle: software should be efficient, transparent, and designed with purpose.
Projects / Softwares
We are currently developing and maintaining open-source software, designed with a focus on performance, transparency, and long-term maintainability. These projects are also used as educational materials in higher education, supporting specialized courses and advanced studies in computer science and systems programming.
Claudia
A UNIX-inspired operating system implemented in Zig for the RISC-V architecture.
It is designed as both an educational resource and a practical experiment in POSIX alignment, focusing on clarity and reproducibility.
Source Code
Nyxx
A 6502 CPU emulator with WebAssembly support, built for explicit memory control and predictable execution.
It demonstrates how low-level hardware principles can be expressed in modern programming languages while remaining portable across environments.
Source Code
Dive deeper with C
A technical resource that explains the inner workings of the Linux kernel, from userland interactions to system call handling, with annotated source code references.
It is intended to make kernel-level study more accessible, empowering students to explore real-world systems with confidence.
Read Articles
We share these projects and resources to contribute to the open-source community, encourage learning, and promote a deeper understanding of how software works — from the highest abstractions down to the lowest levels. By doing so, we aim to pass knowledge forward and inspire the next generation of programmers and system architects.
Contact Us
For collaboration, consulting, or educational engagements, please get in touch. We welcome inquiries from individuals, organizations, and academic institutions. Personal introduction as the Lead Programmer is available here. This project is led by @Kei Sawamura and written in Go on Gentoo Linux with Vim.