alt Hacker NewsNethack embeds Lua 5.4.8, so you don't need it installed from a distribution's package manager. As long as your system can build C99* it can build Lua. And given that Nethack 5.0.0 is C99, this dependency is not reducing portability any further.
* Lua has a LUA_USE_C89 flag so it may be more portable than Nethack 5.0.0 at this point.
> LUA_USE_C89
How much functionality/performance does one lose with this flag? Genuine question, I don't know.
If C89 and C99 were equally performant/functional, it would seem logical to just target C89 (since any C99 compiler should be able to compile C89 too). There must be some reason it's a flag.