| Branch | A named line of configuration history forked off a commit. |
| BranchIndex | A local index over the branches in the object store. |
| BranchStore | Creates, lists and removes branches in the object store. |
| MergeBase | Finds the commit two lines of history last agreed at. |
| MergeEntry | What a merge decided about one configuration object, and what it would write. |
| MergePlan | What a merge would do, object by object, before anything is written. |
| Merger | Plans and applies a merge of one config branch back into the trunk. |
| MergeResult | What a merge actually did, against what it planned to. |
| ThreeWayMerge | Merges one configuration object across a base, a target and a branch. |