CISOfy/lynis ? reverse-engineered prompt

Build me a simple open source command line security audit tool for Unix like systems, especially Linux, macOS, and BSD. I want something agentless that runs directly on the machine with no real installation required, so I should be able to clone or download it and run one command to audit the system.

The tool should do a deep security scan, collect general system info, look for weak or risky configuration, spot outdated or vulnerable software packages when possible, and then give clear suggestions for hardening the system. It should also help with compliance style checks for things like ISO27001, PCI DSS, and HIPAA, plus general vulnerability detection.

Please keep it simple, readable, and easy to update. It should feel useful for sysadmins, auditors, and security people, with practical output instead of a fancy interface. If it makes sense, include ways to customize or extend checks later. Look up current docs online if you need to.