Ask HN: Boring technologies and long-term reliability?

There is a post trending on HN asking a question "What will happen to React after Facebook layoffs". At present I am evaluating tech stack for my project. And that got me thinking, what are the components of software stack that are not hinged to few companies and have long-term survival possibility. Some of the things that come to mind are Postgres, Python, Linux Kernel, BSDs, LLVM, GCC, C++, C, JavaScript, jQuery, GTK, KDE. What else?