Levels of continuous integration

Question

In a recent interview, I was asked about the level of Continuous Integration practiced in our company. When I started describing what we did, the interviewer interjected and asked me the level number - sounded something like CMM level to me. When I told him that I was not aware of any levels followed in my current company, he seemed displeased at my answer.

I am not able to find any such information online.

Can someone please throw some light?

Answer 1

I am afraid the interviewer was not competent at what he was asking. Such interviewers would ask you

Why are manhole covers round?

And they expect you to say something along the lines of safety. But they would completely disregard other valid answers, such as the ones described here

There are no strictly defined levels as such. Merely some bloggers shared their personal view on the topic. Does it really matter if you are on Level A, Stage 2, or Phase III based on their private classification? No it does not. Shall you be aware of such classification to do CI properly? No, you should not.

The actual number is irrelevant, what is relevant is the description of CI process.

Answer 2

I agree that it was a bad interview question but some people have been talking about a maturity model for Continuous Delivery (with 5 levels). For example, take a look at

http://www.infoq.com/articles/Continuous-Delivery-Maturity-Model

Answer 3

Presently in the industry maturity levels for Continuous Integration are sort of customized. Some companies have maximum levels of 6 while some companies like mine follow 5 levels. Continuous Integration concept was envisaged at ThoughtWorks and if you go through this document on their website you'll see they too follow a model of 5 levels.

P.S - It indeed was a vague interview question.

Answer 4

It sounds like your interviewer was asking about CMMI (Capability Maturity Model Integration)]1.

The levels here have very specific meanings, and are used to indicate the level of process maturity within an organization or team. I've never actually worked anywhere that has cared about CMMI, but if you are applying to a company where this is used, or where their clients use this, it may be important to them.

It sounds to me like the interviewer wanted to know if you knew about this at all, and could explain about the different levels. However, as mentioned previously, knowing about Continuous Integration and why it is good for your project (and when it can be bad) is the important piece to pull out. Not whether you've memorized the Wikipedia page on CMMI.