Abstract: Decentralized ridesharing systems and methods for assigning a user request to a particular registered vehicle. The method includes organizing a geographic area into a plurality of geographic zones, each of the plurality of geographic zones serviced by a corresponding regional server, each regional server monitoring a location and a passenger status of one or more registered vehicles within a corresponding geographic zone, and allocating dispatching and ridesharing tasks between the regional servers and the one or more registered vehicles within each of the geographic zones, wherein the regional servers and the one or more registered vehicles are each equipped with decision-making modules powered by a graph neural network with reinforcement learning.