Augeas is a library and command line tool for programmatically editing configuration files in a controlled manner. Augeas exposes a tree of all configuration settings and a simple local API for manipulating the tree. Augeas then modifies underlying configuration files according to the changes that have been made to the tree; it does as little modeling of configurations as possible, and focuses exclusivley on transforming the tree-oriented syntax of its public API to the myriad syntaxes of individual configuration files.