How to version products inside monorepo?

Question

I have been educating myself about monorepos as I believe it is a great solution for my team and the current state of our projects. We have multiple web products (Client portal, Internal Portal, API, Core shared code).

Where I am struggling to find the answer that I want to find is versioning.

What is the versioning strategy when all of your projects and products are inside a monorepo?

• 1 version fits all?
• Git sub-modules with independent versioning (kind of breaks the point of having a mono repo)
• Other strategy?

And from a CI perspective, when you commit something in project A, should you launch the whole suite of tests in all of the projects to make sure that nothing broke, even though there was no necessarily a change made to a dependency/share module?

Answer 1

What is the versioning strategy when all of your projects and products are inside a monorepo?

I would suggest that one version fits all for the following reasons:

• When releasing your products you can tag the entire branch as release-x.x.x for example. If bugs come up you wouldn't need to check "which version was of XXX was YYY using"
• It also makes it easier to force that version x.x.x of XXX uses version x.x.x of YYY. In essence, keeping your projects in sync. How you go about this of course depends on what technology your projects are written in.

And from a CI perspective, when you commit something in project A, should you launch the whole suite of tests in all of the projects to make sure that nothing broke, even though there was no necessarily a change made to a dependency/share module?

If the tests don't take particularly long to execute, no harm can come from this. I would definitely recommend this. The more often your tests run the sooner you could uncover time dependent or environment dependent bugs.

If you do not want to run tests all the time for whatever reason, you could query your VCS and write a script which conditionally triggers tests depending on what has changed. This relies heavily on integration between your VCS and your CI server.