Add Cycle Validation

[mikelikespie]

Right now, if there's a dependency cycle, one will get a stack overflow at runtime. This isn't great and needs to be fixed.

When implementing this feature, we need to be extra careful to surface actionable error messages since debugging a cycle can be very hard.

[sebastianv1]

Closing because this issue hasn't received any activity lately, feel free to reopen if it's still an issue.