I’ve been trying to find where the logs are being written but I suspect the std is being redirected to the UI without saving that into a file (because of the size limit of the app).
I recommend to use your own logger and output that into a file that you can tail in the instance console.
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Yup, Glitch has a package under /etc/debugger to redirect logs through a proxy, they are not being written in a file so you’ll have to debug it yourself.
I sometimes use Winston for running my own logger to a separate file - this will only log stuff you call from the winston logger instance but it might help you on your journey! I just made https://glitch.com/edit/#!/starter-winston?path=server.js:6:1 where you can see a starting point for using it.