Wonderlic - Wonderlic offers pre-employment tests and student selection assessments.

Colaboratory - Free Jupyter notebook environment in the cloud.

HackerRank - HackerRank is a platform that allows companies to conduct interviews remotely to hire developers and for technical assessment purposes.

Numerai - Hedge fund that crowdsources market trading from AI programmers over the Internet

Codility - Codility provides a SaaS platform with advanced validation, security and protection features to evaluate the skills of software engineers.

Kaggle - Kaggle offers innovative business results and solutions to companies.