Over 100 forks of deliberately vulnerable web applications and APIs to practice on.
Like a CTF, but for sysadmins. They give you a server with at least one problem; troubleshoot and fix it. Great practice for tech interviews.
The Capsulecorp Pentest is a small virtual network managed by Vagrant and Ansible. It contains five virtual machines, including one Linux attacking system running Xubuntu and 4 Windows 2019 servers configured with various vulnerable services. This project can be used to learn network penetration testing as a stand-alone environment but is ultimatly designed to complement my book The Art of Network Penetration Testing.
vAPI is Vulnerable Adversely Programmed Interface which is Self-Hostable PHP Interface that demonstrates OWASP API Top 10 in the means of Exercises. Requires PHP, Apache, MySQL, and probably a man-in-the-middle proxy.