Tenant code debugging in multi-tenant systems

Systems and methods for debugging tenant code for a multi-tenant system. A tenant code debugger may be installed on a user computing device, and connected to the multi-tenant system over a stateful connection. When an interested event occurs, the multi-tenant system may route execution to the user computing device for local debugging. A proxy may be used for the communications between the tenant code debugger and the multi-tenant system. When interaction with the multi-tenant system is needed, a request may be sent to the multi-tenant system which may interpret the request, execute to fulfill the request, and send the result back to the tenant code debugger, so that execution of the tenant code can be continued in the user computing device. The tenant code is uploaded to the multi-tenant system after debugging.