Question:
I joined today and saw a message that I can upgrade my repl to the nix system and now I lost almost all my files. How Can I revert that?
Replit Profile: https://replit.com/@xWonder87x
Welcome to the community 
You can restore them by making files with the same names as the deleted files.
If the content is empty on some of the files, you can open the file and click the History button on the bottom right. Use the slider to go back to previous versions of your file.
Hope this helped you 
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