Bounties & CTFs
Potential bounty programs and competitions to improve skills.
Maximum bounty is $2500, codeQL is a good tools to found issues with open source projects.
Minimum bounty is $500, and this is a great way to learn OSQuery.
OSCP Relevant Machines
'Rooms' meant to teach you a set of skills, or King of the Hill competitions where you fight to maintain control of a machine