Computer security is a whole-system property – "the system is as secure as its weakest link". With broad adoption of secure software development practices, such as memory safety techniques, the adversaries shift their attention to exploiting whole-system weaknesses such as side channels and glitch attacks. Conventional approaches to system building using both vertical and horizontal composition cannot protect against these threats. For example, timing attacks pierce through the entire system stack. This talk presents our project on using state of the art techniques against such advanced threats with the target goal of building secure OS abstractions and how to develop software for such systems