An explanation of primary and secondary constructors, and how Kotlin ensures your object instances are well-initialized: https://zsmb.co/primaries-matter-a-discussion-of-constructors/

There can be a class with no primary constructor, where all constructors are secondary ones.

Thanks for this comment, I somehow completely forgot about this when writing the article. I've added a new section about it now.

Sorry, but I don't see that new section

Damn, I had a bad deploy of the site that nobody pointed out to me until now, and I completely forget to check how it went live. Thanks again, the section really really is there now 🙂 https://zsmb.co/primaries-matter-a-discussion-of-constructors/#without-primaries