We had an interesting discussion the other day about what made a “good” DevOps tool.  The assertion is that a good citizen or good “link” in the toolchain has the same basic attributes regardless of the part of the system for which it is responsible. As it turns out, at least with current best practices, this is a reasonably true assertion.  We came up with three basic attributes that the tool had to fit or it would tend to fall out of the toolchain relatively quickly. We got academic and threw ‘popular’ out as a criteria – though supportability and skills availability has to be a factor at some point in the real world. Even so, most popular tools are at least reasonably good in our three categories.

Here is how we ended up breaking it down:

1. The tool itself must be useful for the domain experts whose area it affects.  Whether it be sysadmins worried about configuring OS images automatically, DBAs, network guys, testers, developers or any of the other potential participants, if the tool does not work for them, they will not adopt it.  In practice, specialists will put up with a certain amount of friction if it helps other parts of the team, but once that line is crossed, they will do what they need to do.  Even among development teams, where automation is common for CI processes, I STILL see shops where they have a source control system that they use day-to-day and then promote from that into the source control system of record.  THe latter was only still in the toolchain due to a bureaucratic audit requirement.
2. The artifacts the tool produces must be easily versioned.  Most often, this takes the form of some form of text-based file that can be easily managed using standard source control practices. That enables them to be quickly referenced and changes among versions tracked over time. Closed systems that have binary version tracking buried somewhere internally are flat-out harder to manage and too often have layers of difficulty associated with comparing versions and other common tasks. Not that it would have to be a text-based artifact per se, but we had a really hard time coming up with tools that produced easily versioned artifacts that did not just use good old text.
3. The tool itself must be easy to automate externally.  Whether through a simple API or command line, the tool must be easily inserted into the toolchain or even moved around within the toolchain with a minimum of effort. This allows quickest time to value, of course, but it also means that the overall flow can be more easily optimized or applied in new environments with a minimum of fuss.

We got pretty meta, but these three aspects showed up for a wide variety of tools that we knew and loved. The best build tools, the best sysadmin tools, even stuff for databases had these aspects. Sure, this is proof positive that the idea of ‘infrastructure as code’ is still very valid. The above apply nicely to the most basic of modern IDEs producing source code. But the exercise became interesting when we looked at older versus newer tools – particularly the frameworks – and how they approached the problem. Interestingly we felt that some older, but popular, tools did not necessarily pass the test.  For example, Hudson/Jenkins are weak on #2 and #3 above.  Given their position in the toolchain, it was not clear if it mattered as much or if there was a better alternative, but it was an interesting perspective on what we all regarded as among the best in their space.

This is still an early thought, but I thought I would share the thought to see what discussion it would stimulate. How we look at tools and toolchains is evolving and maturing. A tool that is well loved by a particular discipline but is a poor toolchain citizen may not be the right answer for the overall organization. A close second that is a better overall fit might be a better answer. But, that goes against the common practice of letting the practitioners use what they feel best for their task. What do you do? Who owns that organizational strategic call? We are all going to have to figure that one out as we progress.