OWASP Coraza WAF is a golang modsecurity compatible firewall library
Coraza is an open-source, enterprise-grade, high-performance Web Application Firewall (WAF) ready to protect your beloved applications. It is written in Go, supports ModSecurity SecLang rulesets and is 100% compatible with the OWASP Core Rule Set. Coraza is a drop-in alternative to replace the soon-to-be abandoned Trustwave ModSecurity Engine and supports industry-standard SecLang rule sets. Coraza runs the OWASP Core Rule Set (CRS) to protect your web applications from a wide range of attacks, including the OWASP Top Ten, with a minimum of false alerts. ...
Cross-platform C++ libraries with a network/internet focus.
NOTE: Current source code as well as bugs/patches are on GitHub:
https://github.com/pocoproject/poco/
C++ class libraries for network-centric, portable applications, integrated perfectly with the C++ Standard Library. Includes network protocols (Sockets, HTTP, FTP, SMTP, POP3, etc.), SQL database access and XML parsing. Licensed under Boost license.
NetTool is a developer tool for monitoring and manipulating application-level network messages, particularly useful for debugging web applications and web services. There are two components to NetTool: the HTTP Client, and the TCP Tunnel.
Flea2Flea is a pocket web server written in Java which enables ad-hoc peer-to-peer file sharing with anyone who has an http client (web browser). Files are only accessible while you are running Flea2Flea. You have absolute control.