"Compiling" throws me off a bit, because I usually think of that as a process that bakes in everything except for I/O. It seems like for Dhall, this is done on-demand, like an interpreter, and so the result of execution could change if the contents of the referenced files change. But I'm not certain how this would extend to ahead-of-time compilation. Would you have to mark file references by whether they are to be read at compile-time or run-time?