OWASP Coraza WAF is a golang modsecurity compatible firewall library
Free UTM appliance: firewall, VPN, WAF and antivirus in one ISO.
SKUDONET Open Source Load Balancer and Web Application Firewall
Next-generation and open-source Web Application Firewall (WAF).
Web security protection system based on openresty
Powerfull Web Application Firewall for PHP
Free Web Application Firewall