WEB SERVERS
I have installed and configured these and other httpd software.
In the case of apache , I most often install from source. The latter one Formula_One, was actually a web server I wrote from scratch. I've also written loadable modules such as Netscape's NSAPI applied to tasks such as customized treatment of user logins, providing centralized user authentication to multiple http servers against a centralized backend. Another example would be the addition of internal parsing of new html file types.

NCSA ApacheFormula_One
NetscapeTomcat  
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