Secure software delivery

Experimental Python C++17

The pw_software_update module offers the following building blocks for setting up your own end-to-end software delivery system.

  • TUF embedded: An underlying TUF-based security framework tailored for embedded use cases that enable safe and resilient software delivery.

  • One bundle: A standard update bundle format for assembling all build artifacts and release information.

  • Two keys: Each product has two keys dedicated to software updates. The targets key directly signs a versioned manifest of target files and can be regularly rotated by the root key. The root keys are in turn rotated by verified boot. No provisioning is required.

  • Frameworked client: An update client that takes care of all the logic of checking, staging, verifying, and installing an incoming update. The framework calls into the downstream backend only when needed.

  • Signing service: Integration support for your favorite production signing service.

  • Tooling: Python modules that assemble, sign, and inspect bundles, ready to be integrated into your build and release pipeline. Plus a CLI with which you can try out pw_software_update before buying into it.

  • Extensive guidance: All software update systems are not equal. We are building out extensive guidance for representative scenarios.

Who is it for#

The pw_software_update module is still in early stages. It works best if your software update needs checks the following boxes.

I want security-by-design!

The pw_software_update module is built with security in mind from day 0. It leverages the state-of-the-art and widely used TUF framework. With relatively little expertise, you can set up and operate a software building, release, and delivery pipeline that is resiliently secure and private.

My project has verified boot.

Software update is an extension of verified boot. Security measures in pw_software_update CANNOT replace verified boot.


Verified boot, also known as secure boot, refers to the generic security feature that ensures no software component is run without passing integrity and authentication verification. In particular, verified boot ensures the software update stack has not been tampered with.

My project DOES NOT require delta updates.

pw_software_update packages every new software release in a single opaque bundle. The bundle is the smallest granularity transferred between endpoints.

I can manage signing keys myself.

We don’t yet have a public-facing signing service.

I can store and serve my own updates.

We don’t yet have a public-facing end-to-end software delivery solution.

If your project doesn’t check all the boxes above but you still wish to use pw_software_update. Please email or chat with us for potential workarounds.