Gilt
Gilt is a tool which aims to make repo management, manageable. Gilt clones repositories at a particular version, then overlays the repository to the provided destination. An alternate approach to "vendoring".
What makes Gilt interesting, is the ability to overlay particular files and/or directories from the specified repository to given destinations. Originally, this was quite helpful for those using Ansible, since libraries, plugins, and playbooks are often shared, but Ansible's Galaxy has no mechanism to handle this. Currently, this is proving useful for overlaying Helm charts.
Alternatives
History
This project is a golang port of Gilt, and aims to correct poor decisions made in the python version, primarially around config syntax, portability, and reproducibility.