Lua (LuaJIT really) is battle-tested to the extreme and utterly reliable at this point (it's used all over the place, including in the game industry). Guile is

Lua (LuaJIT really) is battle-tested to the extreme and utterly reliable at this point (it's used all over the place, including in the game industry). Guile is still very much focused on Linux and has well-documented issues on other platforms (including Windows and macOS) not to mention absence of developers and users. For all the talk about it being the "official" extensibility language of the GNU project, my understanding is that Guile has a minimal userbase. Finally, having used both Guile and LuaJIT, I have to say that LuaJIT FFI blows Guile FFI out of the water. It's so much better in every possible way. I haven't tested Guile 2.9.1 but I wouldn't think it comes close to LuaJIT in performance either. Embedding Lua or LuaJIT is a piece of cake too, since it has no dependencies whatsoever. Guile loses here too: $ port deps luajit luajit @2.0.5_0 has no dependencies. $ port deps guile Full Name: guile @2.2.4_0 Build Dependencies: gsed Library Dependencies: readline, gettext, libiconv, libtool, gmp, libunistring, boehmgc, libffi, ncurses, pkgconfig So, empirically speaking, I don't see Guile as an alternative to Lua. It simply can't compete.