Ranked in these QuestionsQuestion Ranking
Pro Continuous configuration - dedicated to production
Rudder checks every rule that has been set up to keep it compliant over time. It is a tool made to be used in production. It's not a dev tool where there is no continuity constraint.
Pro Web UI + CLI + API
There is 3 ways to use Rudder. The biggest surprise is that everything that can be done with code is also possible with the web interface, without knowing anything about development or automation, generally speaking.
Pro Light agent developed in C - up to 10 000 nodes
The agent has nearly no impact concerning resources and that is the reason why Rudder is able to manage thousands of servers without any performance issues.
Pro Codeless user interface with built-in template library and editor
Non-expert users can define parameters in a central interface, and Rudder will automatically make sure that IT services are installed, configured, running and in good health. All actions (checks, warnings, fixed errors…) are reported upon immediately in the user interface, keeping drift from nominal behaviour low.
Pro Free and open source
Apart the agent on proprietary OS (AIX, Windows, ...) , Rudder is an open source and free software. This means that the code source is available on Github for every part of Rudder (Rudder webapp, and every other Normation repository). This also means that packages for a wide range of distributions are released and available to download freely.
Pro Running on Linux, Windows, AIX, Solaris, Android...
Rudder can manage quite everything. So far only HP-UX and iOS don't have their own agent version, but everything else is available already.
Con Community growing but not very big at this day
There is more and more people getting involved in the Rudder community, but it's nothing compared to Puppet community so far.
Con Not a one-shot deployment tool
Rudder is overkill if the goal is only to push one-time actions. Thankully, a plugin is available to connect Rudder with Ansible and enhance its capability.