Have a look at e.g. https://sbabic.github.io/swupdate https://sbabic.github.io/swupdate, which is also available in Buildroot; kernels and rootfs can be configu

Have a look at e.g. https://sbabic.github.io/swupdate https://sbabic.github.io/swupdate, which is also available in Buildroot; kernels and rootfs can be configured to be rather small.