Hi there,
If you’re having building troubles, this article is the best place to start reading: [Support Guide] Debugging Netlify site builds . Over 99% of problems we find are covered in that article. It has next steps as to what you should let us know after you’ve run through all the things in the article like setting appropriate versions/variables at Netlify to help us match your local.
If you need to see a debug log like that (tip: you probably don’t; the advice in the article I linked is likely to clear up the problem), you can use a pattern like this for a build command:
npm run build ; cat /opt/buildhome/.npm/_logs/*-debug.log ; sleep 200 ; false
This build command will ALWAYS cause your build to fail instead of being published, but will output the file before doing so, so you can read it.
Or, you could build locally inside our build environment, using these tips: GitHub - netlify/build-image: This is the build image used for running automated builds - which will let you read the log directly yourself after the build fails.