epubcheck is written in Java, and thus can't be embedded into Sigil. FlightCrew is in C++, and thus can be. This was the main driving force.
Originally Posted by GRiker
Valloric, thanks for making FlightCrew available.
The GUI works as advertised, but I can't figure how to invoke the CLI version. From the project site docs, it suggests that the GUI version includes the CLI.
How do I invoke the CLI version?
The GUI package
includes the CLI, which is a separate application called FlightCrew-cli.
Except on Mac, because I just remembered I forgot to put in the DMG.
Originally Posted by kovidgoyal
Cool, hopefully the beginning of the end of epubcheck.