SPARK user Alexander Senier recently presented their use of SPARK for building secure mobile architecture at BOB Konferenz in Germany. What's nice is that they build on the guarantees that SPARK provides at software level, using them to create a secure software architecture based on the Genode operating system framework. At 19:07 in the video he presents 3 interesting architectural designs (policy objects, trusted wrappers, and transient components) that make it possible to build a trustworthy system out of untrustworthy building blocks (like a Web browser or a network stack). Almost as exciting as Alchemy's goal of transforming lead into gold!
Their solution is to design architectures where untrusted components must communicate through trusted ones. They use Genode to enforce the rule that no other communications are allowed and SPARK to make sure that trusted components can really be trusted. You can see an example of an application they build with these technologies at Componolit at 33:37 in the video: a baseband firewall, to protect the Android platform on a mobile device (e.g., your phone) from attacks that get through the baseband processor, which manages radio communications on your mobile.
As the title of the talk says, for security of connected devices in the modern world, we are at a time "when one beyond-mainstream technology is not enough". For more info on what they do, see Componolit website.