rosdep

rosdep is a command-line tool in the Robot Operating System (ROS) that automates the installation of operating system dependencies required by ROS packages. It translates dependencies declared in a package manifest into the appropriate system packages for the target operating system, providing a uniform way to prepare a build environment across platforms.

The tool relies on a central rosdep database of rules that map ROS dependency names to OS-specific package names. Each rule is associated with a particular operating system and package manager (for example apt on Debian/Ubuntu, dnf or yum on Fedora, zypper on openSUSE, and brew on macOS). When run, rosdep analyzes the dependencies of a package or workspace, resolves them using the rules, and issues the necessary install commands. Users can update the rules with rosdep update and perform dry runs to see what would be installed.

Common usage includes rosdep update to refresh the database, and rosdep install --from-paths src --ignore-src -r -y to install dependencies for packages located in a path. rosdep check can be used to verify dependencies without installing. Packages may include rosdep rules that describe how to install their system dependencies on different OSes, enabling cross-platform setups.

rosdep focuses on system-level dependencies and does not install the ROS software itself. It may require sufficient privileges to install packages, and some dependencies may not have equivalents in all OS repositories, requiring manual installation or custom rosdep rules. The tool is used in both ROS 1 and ROS 2 workflows to streamline dependency management and environment setup, aiding reproducibility across development environments.