Sphere Online Judge (SPOJ) - Problems
CodeAbbey - programming problems
H-99: Ninety-Nine Haskell Problems - HaskellWiki
L-99: Ninety-Nine Lisp Problems
Codecademy
DevDocs API Documentation
Full stack open
Learn to code with Scrimba
Developer Roadmaps - roadmap.sh
Your Career in Web Development Starts Here | The Odin Project
freeCodeCamp.org
MDN Web Docs
W3Schools.com
Exercism
LeetCode - The World's Leading Online Programming Learning Platform
Edabit
Rosetta Code
Codewars - Achieve mastery through coding practice and developer mentorship
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