It will depend on which implementation specific behavior a given library uses. For example, guile has `#{}#` syntax for verbatim atoms. If a library uses that i

It will depend on which implementation specific behavior a given library uses. For example, guile has `#{}#` syntax for verbatim atoms. If a library uses that it will not work on any other scheme. Guile and gambit also have divergent behavior when e.g. parsing char literals `#\)a` parses correctly in guile but not gambit, and on the other hand `'a'b'c` reads as `c` in gambit but `a'b'c` in guile. And these are just issues with variant behavior in the reader. The list of these kinds of edge cases is long so it probably winds up being easier to try to just run a library to see if it works. I doubt anyone has done a systematic survey.