Systems and methods for a history walker interface to a time-based data structure are disclosed. A time-based data structure may contain information about updates to a set of records that change periodically over time. For example, a set of records that record state transitions of a task item as the task item progresses through its life cycle. An example task item may be represented by a change request or incident report in a help desk software application. The task item begins with an “open” state and may transition through any number of states (e.g., assigned, on-hold, test, customer response requested, etc.) on its way to ultimately being “closed” as completed. A history walker interface may assist application developers when creating applications to indicate how the task item transitioned through its different states throughout its lifecycle.