LabSim was developed by Aeonic, with the majority of the coding done by Eshaan Bhargav Patel. LabSim, formerly Proboxels, was initially started as a mod of the game Sandboxels by R74n, before gradually improving into a fully fledged fork of Sandboxels version 1.4 and from that into a separate program altogether fully separate from Sandboxels.
People who did make minor contributions include Aaron D'souza, Brenden D'souza, and Pravar Gollamudi.