"Friendship is optimal" (https://www.fimfiction.net/story/62074/Friendship-is-Optimal)
And
"the metamorphosis of Prime Intellect (https://web.archive.org/web/20040401174623/http://www.kuro5h..., strongly NSFW)
Both are stories about a singularity that turns the world into a simulation, in which some can program the simulation.