Comment by aragilar

I'm not sure what you think specifically needs maintaining, it's the same as LAMP, LEAN, JAM and the various stack acronyms? The BSD you choose is naturally maintained by the various BSD distros (though there's an implicit assumption of OpenBSD as will become obvious), C is C (so defer to your C-complier), httpd comes from OpenBSD (https://man.openbsd.org/httpd.8), and SQLite is SQLite. You can naturally choose to add additional libraries (some are suggested on the site, I don't know what their status is, but the article includes libcurl and libsodium, which are also well maintained), but as the example shows, you don't need much to start with. A key thing that's a bit hidden is the use of CGI and the various OpenBSD hardening tools (e.g. pledge, unveil), which make exploiting the C binary much harder than on other systems.