The nixpkgs-unstable channel's programs.sqlite was used to identify
packages producing exactly one binary, and these automatically added
to their package definitions wherever possible.
Without the change build fails against `gcc-13` on `master` as
https://hydra.nixos.org/build/246520454:
In file included from /build/source/src/actor.h:40,
from /build/source/src/g_blake/a_smartanim.cpp:36:
/build/source/src/gamemap.h:255:64: error: 'std::uint16_t' has not been declared
255 | void OperateConcession(std::uint16_t concession);
| ^~~~~~~~
Without the change build fails as:
/build/source/src/wl_net.h:38:10: fatal error: SDL_net.h: No such file or directory
38 | #include <SDL_net.h>
| ^~~~~~~~~~~
compilation terminated.