Systems and methods for making source code annotations available across software code repository commits are disclosed. An example method for creating an incremental blame structure for determining which annotations should be shown begins with receiving a commit including at least one file that has been updated with respect to a parent commit. Then, parent file revisions for the at least one file should be identified. An example method determines the differences between the at least one file and the identified parent file revisions and traces an origin of each line in the file based on the determined differences. An identifier of the line and the line's origin may be added to the incremental blame data structure of the file.