A key ceremony application creates bundles for custodians encrypted with their passphrases. Each bundle includes master key share. The master key shares are combined to store an operational master key. The operational master key is used for private key encryption during a checkout process. The operational private key is used for private key decryption for transaction signing in a payment process. The bundles further include TLS keys for authenticated requests to create an API key for a web application to communicate with a service and to unfreeze the system after it has been frozen by an administrator.