Development

Refactoring & patterns -> https://refactoring.guru/ Teach Yourself CS -> https://teachyourselfcs.com/

• Java
• Python
• Web development

Java

https://apprize.best/javascript/oca_2/13.html

Python

https://github.com/jpmorganchase/python-training 

Web development

Pages for reference:

http://www.awwwards.com/