We recommend the spelling InnerSource.
We encourage you to use the word as a proper noun (like “We use InnerSource in that repo.”) wherever possible. We discourage the use of verb forms of the word (like “We’re InnerSourcing that repo”).
InnerSource is an artificial term that does necessarily have a spelling that would naturally be correct. Therefore you will find various spellings when you search for the term online.
We favor the spelling InnerSource, for the following reasons:
- That’s the way Tim O’Reilly spelled it in 2000 (he was into Perl and camel-case was a thing). Also see the Foreword of the Adopting InnerSource book for more of Tim O’Reilly's own words on the topic.
- If you set up side-by-side Google searches for “Inner Source” and “InnerSource” you will find that you get more hits on the former term, by only 1% of them have anything to do with what we call InnerSource. The latter term will be 100% cogent to your inquiry.
- The OSI was denied trademark on the term “open source” because it was made up of two common and unrelated terms. “InnerSource” on the other hand is a new word.
You are right, it isn't consistent. Not yet! But we are getting there. :)
The reason you see multiple spellings in our documentation is that it was built over a period of years during which our thinking on the spelling crystallized.
For new patterns we stick to the spelling InnerSource. Old patterns will be reworked over time to use this spelling as well.
Some people have had a hard time with the camel-case term InnerSource because they’re not sure how to use it in a sentence grammatically.
We recommend not to turn the term into a verb, but rather using it as a noun or adjective.
Recommended use:
“We use InnerSource in that repo.”
“We use InnerSource methods in that repo.”
“We follow InnerSource development methods in that repo.”
“We published the repository as InnerSource.”
Not so good:
“We’re InnerSourcing that repo.”