Vault

Many applications have sensitive data that must have additional storage protection relative to other data. For example, your application may access external services with an "API Key". This key is issued to you by that specific external service provider, and you must keep it safe from being stolen or leaked. If someone got their hands on your payment processor key, for example, they may be able to use it to send money or digital assets out of your account to someone else. Wherever this key is stored, it would make sense to store it in an encrypted form.