Delivery 2 deleted the move and chain_moved, so the layout of the builds under their modules is made by the controller's start (LayBuildsOut), recorded by the key layout.done in the builds bucket, retried every half minute with an urgent condition while it fails; the chain on the bus is refused until it exists. Its source readers use the module and pointer reads.
Every method of builds, build requests, rollouts, merges and assignments reads and writes the chain alone: the else branches that read the tables, the movers and MoveChain with their tests, chain_moved reads, ChainReads and the flags that switched a kind, the store's assignments mirror (KeepAssignmentPlans needs none of it: it uses only the AssignmentMirrored type, mirrors.go, and AssignmentValues, provisioning.go) and its tick, the move code of the controller's start, and ForTest's chain_moved row. The listed store tests of the move go with their functions; the tests of the readers, requests, assignments and plans that lived beside them stay in chain_store_test.go. Tests that replayed old data migrations over the build, assignment and pin tables are removed with the tables. The static test that no plan is written but through SavePlansMoving now reads the plan's chain path.
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