SQL (even if just SQLite) as databases open up a lot of power.
Vim or Emacs for powerful text editing.
A low level language. Sometimes Python doesn't cut it, or it is pretty suboptimal. If you're writing a trading bot, is speed of execution not important?
Operating System knowledge can be helpful at times. I bought one of the No Starch books "How Linux Works" and it is very helpful.
The command line and by that I guess you should know the common Linux commands (cat, grep, sort, uniq, head, tail, ls, top) if you use Linux and how to chain them together via pipes. To give some context, I can write one command which would require 8 lines of Python (saves you valuable time). If you use Windows, learn enough Powershell to be comfortable with it. On occasion I'll use Powershell over Python even though it is dirt slow for reading files.
Firmly agree -- I'm pretty sure I've said it elsewhere, this was a transformational course for me.
I got my start in product support where a lot of our problems could be solved in SQL. We were encouraged to learn it, but most people were happy with the most basic syntax for DML. I worked through the entirety of Dr. Widom's course and it gave me the fundamental data understanding to be a real value to the teams I've worked for, and I used that opportunity to transition into being a full time developer.
Vim or Emacs for powerful text editing.
A low level language. Sometimes Python doesn't cut it, or it is pretty suboptimal. If you're writing a trading bot, is speed of execution not important?
Operating System knowledge can be helpful at times. I bought one of the No Starch books "How Linux Works" and it is very helpful.
The command line and by that I guess you should know the common Linux commands (cat, grep, sort, uniq, head, tail, ls, top) if you use Linux and how to chain them together via pipes. To give some context, I can write one command which would require 8 lines of Python (saves you valuable time). If you use Windows, learn enough Powershell to be comfortable with it. On occasion I'll use Powershell over Python even though it is dirt slow for reading files.