A method, and associated computer system and computer program product. A change of runtime code is detected by one or more processors of the computer system. The change is detected in a debugging session on a first machine. The runtime code is obtained from source code that is developed on a second machine that is different from the first machine. In response to the change being detected, a portion of the source code associated with the detected change is determined, by the one or more processors, based on a profile. The profile indicates a mapping between the source code and the runtime code. The portion of the source code is caused, by the one or more processors, to be updated based on the detected change in the runtime code.