Berkshelf
A cookbook source structure manager for Chef, similar to Bundler for Ruby. Each Chef cookbook can be structured as an individual entity and can be pulled into your main Chef workflows.
linux windows osx open-source scm ruby
GitLab
GitLab is an open-source, fully featured git web frontend developed using Ruby on Rails. You can host this in your own server, create projects, repositories and teams, manage fine grained access permissions, add wikis, collaborate, raise and merge pull requests, and do much more through the web! (Note: GitLab acquired Gitorious, another open source git management system, in March 2015)
linux open-source vcs ruby
Librarian-Puppet
Librarian-Puppet is a source structure and dependency manager for Puppet modules, similar to bundler for Ruby. Each Puppet module can be managed as a separate source repository with individual versioning, and can then be pulled into your Puppetfile.
linux windows osx open-source scm ruby
Monit
An open source utility for managing and monitoring processes, programs, files, directories and filesystems
linux osx open-source monitoring process-mgmt c
Opskeleton
Bootstrap a DevOps infrastructure with some opinionated defaults (vagrant, puppet, librarian-puppet, git, etc), standard development guidelines, etc. Makes it very quick to get a DevOps team up and running
linux open-source scm virt config-mgmt provisioning orchestration ruby
Review Board
Review Board is a feature packed code review tool for multiple SCM systems (like git, bzr, cvs, subversion, etc).
linux open-source commercial scm python
Supervisor
Supervisor can manage application processes. It can start and stop a group of processes, restart processes if any of them terminate (keep-alive), start multiple instances of the same process (process pooling), automatically manage PID files, and much more! Very useful if you need to manage multiple processes for your application.
linux osx open-source process-mgmt python