Using cryptokit, how is it secure from others

I am creating a key, such as:

let key = SymmetricKey(size: SymmetricKeySize.bits256)

Is it possible for another developer to simply decrypt my files with using CryptoKit ... or how do I provide my own key to ensure that can't happen?

Thanks !

Is it possible for another developer to simply decrypt my files

Only if they know the key. Where are you storing it?

Using cryptokit, how is it secure from others
 
 
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