Spoj - Sphere Online Judge created for the coders' community to train, to learn and to make progress.
Teachable - Create and sell beautiful online courses with the platform used by the best online entrepreneurs to sell $100m+ to over 4 million students worldwide.
99 Interview - 99Interview provide you the platform to prepare the interview before facing the real interview panel.
Clever - syncing between education applications for K-12 schools
HackerRank - HackerRank is a platform that allows companies to conduct interviews remotely to hire developers and for technical assessment purposes.
Claroline - Claroline is a collaborative eLearning and eWorking platform.