Reminds me of a short story called Luminous by Greg Egan. In that story the universe is a declarative system that does have a non-pseudo random component to it -- with actual reality being an emergent phenomenon between this declarative model and the entities within exploring that model by causing the universe to imbue the mathematical objects implied by the universe with specific reality by actually computing them, in so doing "expanding" the size of the universe and introducing new effects from this expansion into the evolution of the system ... in the story it turns out there are multiple actors active at the edge of defining the universe -- and their actions can actually influence the ability of other actors to continue in their participation in the universe creation process ...

Edit: my attempt to elaborate on the idea from the story ... I don't know if I can summarize the concept that well -- I think the framing within the story for the plot is something along the lines of: 1. Mathematical truth exists 2. There is an existential difference between a mathematical truth and a specific occurrence of the "pattern" described by that truth within the physical material of the universe.

I think the eli5 example in the story is based on the integers. You have the integers which are infinite, and you have an instantiated version of some number n if you have an occurrence of n things in nature. The reality of n is fundamentally different if you are in A universe with "n things" vs one with only m things m<n.

I think that's the motivation for the concept -- and in the story a researcher sets off to find scenarios where the universe had not yet "instantiated" one of the "laws" that could be derived from mathematical reality -- and ends up finding out that there is more than one possible way for the laws of "reality" to expand ... -- with different implications on what laws might be discovered in the future ...