meta-updater

Just a quick tip, if you are interested in Yocto, and especially Yocto on the Raspberry Pi: there's a layer called meta-updater[1], originally developed for Automotive Grade Linux, that lets you add over-the-air updates to your Yocto-built systems, and it supports Raspberry Pi. It uses OSTree[2] to give you atomic updates and nice, small update sizes. (The whole filesystem is a content-addressed object store that's hard-linked into the actual directory structure at boot time.) There's also a guide[3] for doing this using HERE's servers for delivering your updates. It's free to use, but if you prefer a free-as-in-speech solution, you can either ignore the update client and run the updates yourself from a bare OSTree repo, or run the open-source community edition[4] of HERE's server software. (Full disclosure: I work for HERE, and wrote the

I'm not sure I buy the embedded/IoT use case; OSTree is a really good model there and is more featureful. The "well, if your filesystem image delta happens to be in the form of a lot of very small files it's not so great for CDNs" doesn't strike me as a terribly good reason to give up everything OSTree gives you (especially with stuff like the meta-updater [1] Yocto integration). [1] https://github.com/advancedtelematic/meta-updater (Full disclosure: I work for Advanced Telematic, the creators and maintainers of the meta-updater Yocto layer.)

If you are interested in OSTree, there is an open-source solution for OSTree updates on embedded devices. Yocto layer: https://github.com/advancedtelematic/meta-updater Quickstart project with a nice tutorial: https://github.com/advancedtelematic/garage-quickstart-rpi And yes, we have chosen it because you don't have to waste twice as much disk space, and, more importantly (for wireless networks at least), you don't have to download the whole image.