A code stream provides a historical view of changes to program code and related actions. The code stream is displayed concurrently with the code for reference, navigation, editing, sharing, and to aid in interruption recovery. The code stream automatically constructs a list of visited code segments based on user changes to the code or navigation within the code. The code stream is an activity history that is constructed based on analysis of user navigation behavior, such as specific edits to the code or dwelling in a section of the code. The user has the ability to undo changes in the code in a non-linear fashion by individually reversing changes from the history listed in the code stream. The user may manually add other non-code items to the code stream.