1. A method for stacking global variables associated with a plurality of tools, comprising: loading a first tool global variable into a memory and executing a first tool of a computer application, the computer application configured to automate human resource processes; responsive to a call to execute a second tool of the computer application, pushing the first tool global variable onto a stack; loading a second tool global variable into the memory and executing the second tool; and responsive to completing execution of the second tool, popping the first tool global variable off the stack and loading the first tool global variable back into the memory.