Docker 1.13.0 promises to be a major release, and the changelog of the first RC build is already huge, suggesting numerous build improvements, such as the ability to specify images that can be used as a cache source during build, the implementation of an experimental option for squashing image layers to the FROM image after a successful build, as well as step number support and “–network ” option to the “docker build” command. There’s also support for compressing the build context when building an image, and unused build-args are now permitted. Moreover, it looks like Docker 1.13.0 will add DEB and RPM builder for the Ubuntu 16.10 (Yakkety Yak) and Fedora 25 operating systems respectively, along with support for building Docker Debian packages (DEBs) for the Ubuntu 16.04 LTS (Xenial Xerus) distro on IBM System z (s390x) and PowerPC (PPC) 64-bit architectures.