Actually in doing some more research - I found that GDAL ( [https://gdal.org](https://gdal.org)/ ) opens grib2s, and some kind of netcdf formats. Not sure if its the specific version you're looking for.
Looks like somebody has already started writing headers for gdal in nim, too: [https://forum.nim-lang.org/t/3417](https://forum.nim-lang.org/t/3417). Maybe I should start there.
