Linux, Apache Webserver, PostgreSQL, LLVM, Clang, GCC, BSD(any flavour), Boost, Rust, GTK, KDE, Firefox, MySQL, MariaDB, Sqlite. I suggested the above projects

Linux, Apache Webserver, PostgreSQL, LLVM, Clang, GCC, BSD(any flavour), Boost, Rust, GTK, KDE, Firefox, MySQL, MariaDB, Sqlite. I suggested the above projects because a lot of people use them in commercial products. So they are not going to go away. And they are very well funded by mega corporations.