Rbundler manages a project-specific library for dependency package installation. By specifying dependencies in a DESCRIPTION file in a project's root directory, one may install and use dependencies in a repeatable fashion without requiring manual maintenance. rbundler creates a project-specific R library in `PROJECT_ROOT/.Rbundle` (by default) and a project-specific `R_LIBS_USER` value, set in `PROJECT_ROOT/.Renviron`. It supports dependency management for R standard "Depends", "Imports", "Suggests", and "LinkingTo" package dependencies. rbundler also attempts to validate and install versioned dependencies, such as ">=", "==", "<=". Note that, due to the way R manages package installation, differing nested versioned dependencies are not allowed. For example, if your project depends on packages A (== 1), and B (== 2), but package A depends on B (== 1), then a nested dependency violation will cause rbundler to error out.