When working with CFEngine, it’s common to hear advice about separating data from policy. Separating data from policy allows for separation of concerns, delegation of responsibilities and integration with other tooling. Each organization is different, and a strategy that works well in one environment may not work as well in a similar environment of another organization, so CFEngine looks to provide various generic ways to leverage external data.

CFEngine is well suited for use in IoT environments due to it’s portability, size, and performance. There already exists a meta layer for including the CFEngine community client and Masterfiles Policy Framework in Yocto Project builds.

CFEngine and Ansible are two

Manually managing groups on a large infrastructure can be a tedious task, and is therefore best suited through automation software like CFEngine. Unfortunately - at time of writing - CFEngine does not have any built-in promise types for managing groups. But fear not; in CFEngine 3.17, custom promise types were introduced.

Using modules, you can add custom promise types to CFEngine, to manage new resources. In this blog post, I’d like to introduce some of the first official modules, namely git and systemd promise types. They were both written by Fabio Tranchitella, who normally works on our other product, Mender.io. He decided to learn some CFEngine and within a couple of weeks he’s contributed 3 modules, showing just how easy it is to implement new promise types. Thanks, Fabio!

I recently had a minor task involving changing an option - on one of our command line tools - from taking a required argument, to taking an optional argument. This should be easy they said; just change the respective option struct to take an optional argument, add a colon to the optstring, and get on with your life. Well, it proved to be easier said than done. My initial expectation was that a solution similar to the one below should just work. And it does work, just not in the way I expected.