There seems to be an alternative to Toolset when it comes to Post Relationships.
It seems a much more powerful one: Posts to Posts by Cristi Burcă, better known as scribu in the WP world.
The plugin can be downloaded on the WP Repo, it has a great documentation, it is around since almost a decade, it is maintained, it allows relationships between posts of the same type!!!, relationships between users and posts, users to users, custom metadata on the relationships, one to many and many to many… erh what? And it is free.
I am not sure what I have been doing with Toolset 
- this plugin seems to be the definition of relationships, and it works about as good as something can work.
Due to its rather minimal GUI implementation - which might scare off users at first - it should also be much more extendable than Toolset. You can even get a version of the plugin that has no GUI at all, and use it as a “core” to your own Theme or Plugin and implement the Relationship GUI however you want.
The only thing I did not like when I look at it was, the coding standard is not my preferred. But that is a detail.
For anyone looking for an alternative - this might just be it?
Has anyone here used this plugin?
I’d love to hear some experience / feedback.
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