We'll we all are humans and Appery.io is by far more responsive than big players that make a lot mistakes . I can help to make a rollout planning since I have experience in banking with this issue.
Just to say Thanks after rollback everything came to normal. I checked out the new mapping and mvc they look good , it would be a nice feature, but maybe a flag for older projects to work with legacy way and then users move to the new environment gradually. It's like having 2 Appery.io workspaces
Like a directive in app settings : use new MVC and Mapping or keep legacy Mapping.
This also would help projects backups to be restored using the Legacy Feature. Then a Window of 6 months for people to migrate to new version. Also selecting users as beta testers for new features would be a nice approach. Just to help
In fact you have already make this approach in the libraries versions usage option. Maybe that can help.
And for the rest of the users... I have lost a lot of money with Microsoft windows crashes , and... Not even an apology received, so be nice with the team. I'm pretty sure you won't find this kind of support on other providers
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