A service proxy services as an application programming interface proxy to a service, which may involve data storage. When a request to store data is received by the service proxy, the service proxy encrypts the data and stores the data in encrypted form at the service. Similarly, when a request to retrieve data is received by the service proxy, the service proxy obtains encrypted data from the service and decrypts the data. The data may be encrypted using a key that is kept inaccessible to the service.