Simultaneous tamper-proofing and anti-piracy protection of software is provided by splitting applications into two parts: an application, and an application launcher. The application is subject to the tamper-proofing protections deployed by a networked service, while the application launcher is subject to anti-piracy protections. To ensure that the application benefits from the anti-piracy protection of the application launcher, the application and application launcher share a trusted challenge-response relationship. The application includes a challenger library for issuing challenges to the application launcher, and the application launcher includes a responder library for responding to such challenges.