Ask HN: As a programmar where to spend my time on unchanging things

As a programmer learning frameworks such as django, ruby on rails, nodejs are usefull but it gets outdated in a few years. What are the things that are worth spending time on which does not change and also might be useful in the future such as mastering Algorithms, datastructures e.t.c

As a web developer I think its worth spending some time to learn about the various protocols in use. Writing your own HTTP server can be a useful learning exercise and is pretty easy a rudimentary server running.

Also I think a deep understanding of JavaScript and concurrent design patterns will be invaluable over the next 5+ years.

Protocols: HTTP, SMTP, FTP, SSH, SCP, RSYNC

Formats: HTML, XML, JSON, CSV, YAML

Languages: SQL, JS, a backend language like Python

Version control: Git, Mercurial

The *nix command line and it's tools: grep etc.

An extensible editor (you only need one) and it's plugins: Vim, Emacs, Sublime, etc.

Social skills: working well with others, working for others, others working for you (aka leadership), conflict resolution, etc.