To debug and troubleshoot the commission calculation engine, a developer can use several tools provided by Salesforce to inspect and pause the execution of Apex code.
Apex Interactive Debugger: It allows real-time debugging of Apex code execution. With this tool, a developer can set breakpoints, step through code, inspect variables, and evaluate expressions.
Developer Console: Although the Developer Console does not allow interactive debugging, it does provide the ability to view logs that capture the execution of code. Debug logs can be inspected to understand the flow of execution and values of variables at different points in time.
Apex Replay Debugger: This tool is part of Salesforce Extensions for Visual Studio Code. It allows a developer to replay a debug log as if they are stepping through the code line by line, which can be very useful to inspect the state of variables at specific points in the execution.
References:
Apex Interactive Debugger
Developer Console Debugging
Apex Replay Debugger