What strikes me, is that everything you listed is under the "Lindy Effect", if it has been around for 30 years, you can expect to be around for the next 30 years.
Among those, I can also recommend:
Relational Databases.
Unix tools for text manipulation, like awk, grep, and sed.
Make.
Architecture patterns.
Among those, I can also recommend: Relational Databases. Unix tools for text manipulation, like awk, grep, and sed. Make. Architecture patterns.