Custom and immutable Linux OS

I am looking to create a custom & immutable Linux OS for my business needs. The main purpose of this OS is for business use. I have some preferences for software, but I am open to suggestions. However, I require advanced customization, including kernel modifications and custom scripts. I am looking for a developer with experience in Linux OS customization and script writing. The ideal candidate should have knowledge of Linux kernel, system calls, and C programming. Additionally, experience in software development for business environments would be a plus.