Methods and apparatus relating to pre-OS (pre Operating System) image rewriting to provide cross-architecture support, security introspection, and/or performance optimization are described. In an embodiment, logic rewrites a non-native firmware interface driver into a native firmware interface driver in response to a determination that sufficient space is available in an integrity cache storage device to store the native firmware interface driver. The logic rewrites the non-native firmware interface driver into the native firmware interface driver by performing one or more of its operations during operating system runtime. Other embodiments are also claimed and described.