Bruise is a place to learn security by doing it. You break into things on purpose, you defend things for real, and you get better at both.
The name comes from color. Red team plus blue team makes purple, and purple teams are the people who understand both sides. That's who Bruise is for.
It mixes guided lessons, where every checkpoint is actually verified, with open-ended challenges where you're on your own, and live competitions for players and teams. It was built first for college cybersecurity classes and competition teams, so instructors can run their classes on it too.
Bruise is built and run by Layer7.