OWASP Coraza WAF is a golang modsecurity compatible firewall library
Intelligently block brute-force attacks by aggregating system logs
Apache 2.4.x security, block known bad IP
pfck - pf check - organizes flow information by host
WordPress IP Address Blocker stops the Spam Visitors & malicious IPs.
A protocol agnostic application layer denial of service attack.
A simple script for distributed computing through PHP: