Why an encrypted config backup breaks when you move servers — and how I fixed it in laravel-config-backup

Imagine you write a letter in a secret code that only your old house key can read. Then you move. You photocopy the coded letter, carry it to the new house… and realise the new key can't decode any of it. The letter is valid, just useless. That's effectively what happens when you back up encrypted values from a Laravel database and restore them onto a different server. I hit exactly this while working on laravel-config-backup today, so here's the problem and the fix. The real cause: Crypt is bound to APP_KEY When you store sensitive settings (think API tokens or OAuth secrets) in the database, you typically encrypt them with Crypt::encryptString() . Lovely — until you remember Crypt uses your app's APP_KEY as the key. A naive backup copies that ciphertext straight across: // Naive approach — move the ciphertext as-is $value = DB :: table ( 'settings' ) -> where ( 'key' , 'some.secret' ) -> value ( 'value' ); // this value is encrypted with the OLD server's APP_KEY The new server has a different APP_KEY . Try to decrypt → DecryptException: The payload is invalid . Your backup is technically complete but practically dead. The fix: decrypt on the way out, re-encrypt on the way in The decision is easy to state, hard to stay disciplined about: never carry ciphertext across a server boundary. Instead — On create : decrypt the values with the source server's APP_KEY , store plaintext inside the archive. Protect that archive with AES-256 and a password (a human-held secret, not the APP_KEY). On restore : re-encrypt the values with the destination server's APP_KEY before writing to the DB. Back to the analogy: you decode the letter, carry the plain letter in a locked briefcase (the password-protected archive), and re-encode it with the new house's lock on arrival. The briefcase handles security in transit — not the old code that's no longer relevant. I made that intent explicit right where the behaviour lives, in ConfigBackupService : /** * Config Backup & Restore. * * Bundl