The document was written against the vendored provider and still said the
storage question was settled that way. Owning the store answered several
of its open questions and deleted others outright, so the corrections are
marked inline the way the rest of the file marks them, rather than
quietly rewritten.
Closed: the Local->Synced migration (account_id is a nullable FK, so
attaching an account is an UPDATE), the recurring-completion model (the
store writes model (a), RECURRENCE-ID overrides sharing the master's
UID), the Auto Backup / cleanUpLists data-loss path, and the lib-recur
version trap. Phase 0's UIDs-at-creation and backup safety are shipped.
The provider-mechanism table is kept as External-mode history rather than
deleted — that code still runs in OpenTasks and tasks.org.
Effort restated: 11.5-15 weeks minus the 2.5-4 owning the store removes,
so roughly 8-11. Also states plainly at the top that no sync code exists
and that ICalendarWriter is the export half of the mapper only.
The vendored dmfs provider was kept on the grounds that it hands us the
sync bookkeeping for free. The phase-1 sync audit measured that
bookkeeping and found most of it broken, absent, or unusable: _DIRTY not
set on delete, no home for a per-collection sync token, read-only
collections inexpressible, ACCOUNT_TYPE write-once so enabling sync is a
full migration, and cleanUpLists able to delete a user's lists after a
backup restore. Sixteen findings are provider-imposed rather than
platform- or protocol-imposed.
Costing the alternative showed the swap is far smaller than assumed.
TasksDataSource is already a 14-method, domain-shaped interface;
exactly one file above the data layer references TasksContract. The
work is a second implementation behind an interface built for it, not a
rewrite. Against ~5 weeks to build, owning the store removes 2.5-4
weeks from the sync plan, and 8,200 of the vendored 14,555 lines are
things we would never write - 23 migrations from a 2013 schema, 798
lines of full-text search the app has zero call sites for, and 1,581
lines of a type-safe layer over ContentValues that Room deletes.
External mode (OpenTasks, tasks.org) is unaffected and keeps every
file that describes somebody else's schema.
STORAGE-DECISION.md is the reasoning; OWN-STORE.md is the architecture
and the six-phase plan. :provider stays in-tree until phase 5 so
recurrence parity can be tested against it before it goes.
Also corrected here: the provider's JVM test count (51 -> 56, measured
from the test-results XML) and a fourth site of the debunked "switching
sync on is never a migration" claim, in StorageMode.kt.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
