etcmanage is a tool for automatically keeping /etc up to date on a BSD system. The key feature which distinguishes etcmanage from other tools is that it will update files without human intervention if the old file has not been modified since last updated and the new file is different. It also supports generating manifests of checksums of files and registering files as unmodified based on a manifest. It requires perl.
etcmanage includes shell scripts BUILD-NetBSD and INSTALL-NetBSD, which are a wrapper around build.sh and an installation script for binary release sets, respectively. Both integrate the use of etcmanage.