sysupgrade is a script to automate NetBSD system upgrades. sysupgrade works by first fetching distribution sets from a specified site or local directory, then by upgrading the system using such distribution sets and later by ensuring that the system configuration is up to date. All the process is controlled by a configuration file, and the defaults should suit the most common NetBSD upgrades. sysupgrade can be used to perform upgrades across different system major and/or minor versions, and it can also be used to track a stable or development branch from the CVS repository. sysbuild is the perfect companion to sysupgrade in those cases where you want to roll your own binaries: both utilities share a very similar command-line and configuration interface, and the default configuration files provide examples on how to integrate one with the other.