I have written an application which I would like to offer via REST API to customers.
In the task which is executed on the server there is some sensitive user data involved, e.g. the user's login to a third party service. There is no way to execute the transaction client side as the code which handles this data must stay proprietary.
Now a user of my API would have to trust me that the service does not steal his data. But is there any way to process such data in a trustless way? I would really like to guarantee my customers that data theft is impossible.