Sumy is an Inky fork that works with the sumi fork of the ink compiler and runtime.

Sumy supports sumi's preprocessor symbols. When editing in Sumy, INKY symbol is enabled by default. When exporting, however, no symbol will be fed to the compiler. You can specify your own symbols with the mainInkFileName.settings.json file:

{
    "inkySymbols": ["INKY", "SUMY", "SUMI"],
    "exportSymbols": ["SUMI"]
}

Here, inkySymbols will be fed to the live compiler when editing, and exportSymbols will be fed to the compiler when exporting json.