Merge engine: a same-parent reorder, an addition under a parent main
deleted, and a branch deleting a container main edited each lost work
silently. Each now follows a policy read from
backend/resources/app/branch-merge-policies.edn, re-read when the file
changes, with the defaults: merge the reorder, and raise a conflict on
the deleted parent or container. Added siblings keep the branch's order.
A :mov-page index counts the target's full page list, a cleared page
background reaches main, a per-attribute resolution can remove an
attribute, and a token set reorder survives a rename on the other side.
Conflict payloads name :main and :branch by document in both
directions. Reorder detection costs nothing measurable on a page of
20,201 objects.
Data versions: each op-log row records the data version it was written
at, the branch replays its log in segments and migrates the document
at each boundary, and the comparison base is migrated like main and the
branch, so an upgrade no longer shows as false conflicts.
Writers: a binfile import, an admin repair, file GC and a snapshot
restore refuse a branch file, whose payload nothing reads, and the
branch base pin cannot be renamed into a user snapshot. A branch save
runs the ordinary media fix-up and logs the rewritten references. An
update from main deletes the branch's copy of media main deleted and
squashes no phantom media changes.
Commands and UI: the pull-request commands publish their messages after
the commit, the listing takes one connection per comparison and shows a
warning instead of "in sync" when a comparison fails, materialize takes
:branch-file-id, and a dashboard fetch that never answers ends in an
error state instead of a spinner, with a refetch on reconnect.
backend/dev/branch_merge_cases.clj builds one example file per merge
policy case for demonstrating the alternatives.
Two models wrote this change, claude-opus-5-5 and mimo-v2.6-pro, and
the work switched between them, so the trailer reads mixed models.
AI-assisted-by: mixed models
This upgrade also includes complete elimination of use spec
from the backend codebase, completing the long running migration
to fully use malli for validation and decoding.
