I’m preparing a substantial refactoring of Racket’s I/O layer just above the OS: https://github.com/mflatt/racket/tree/rktio The Windows part isn’t ready. It’s supposed to work on other platforms – but the 10k lines of code that shifted around are heavily #ifdefed, and I also tried to clean up #ifdefs, so I expect configuration and compilation problems. If you build Racket on anything other than the most common OS distributions, I’d appreciate reports (a reply there here would be good) on whether it builds and/or has build/test errors.