Abstract: A computer system with a command shell that supports execution of commands within transactions. The command shell responds to commands that start, complete or undo transactions. To support transactions, the command shell may maintain and provide transaction state information. The command shell may interact with a transaction manager that interfaces with resource managers that process transacted instructions within transacted task modules to commit or roll back transacted instructions from those task modules based on transaction state information maintained by the shell. Parameters associated with commands can control behavior in association with transaction process, including supporting nesting transactions and non-nested transactions and bypassing transacted processing in some instances of a command.