Software Licenses: GPL, MIT, BSD

What to learn from Open Source projects code ?

Read an article from Medium here: What I learned from reading the Redux source code.

• Does the code use any Lint tool?
• Native Methods
  • When I was looking at the “compose()” function, I ran into an Array method “reduceRight()” that I had never heard of. It made me wonder how many other native functions I haven’t learned.
• Descriptive function names
• How does it handle warnings and errors?
• How does the code improve performance?
• Any package management tool?