When I issue

wget q -O --body-file=LICENSE --method POST --header="Content-Type: text/plain" http://localhost:3000/unattended/failed?token=689ba68a-a511-44b1-bca5-c8f3f1ff353e

I get this error:

Encoding::UndefinedConversionError ("\xE2" from ASCII-8BIT to UTF-8)

Maybe we need something like this:

.encode('utf-8', invalid: :replace, undef: :replace, replace: '_')

Or make sure we get the correct encoding in the first place.