Bridge legacy customer writes to the new identity transactionally
Old clients create cases using a code while new clients use IDs; both must produce equivalent relationships during rollout.
- Focused work estimate
- 3h 30m + prerequisites
- Priority in the scenario
- Medium
- Engineering practice
- Compatibility · Transactions
Estimated field mix
- Database engineering70%
- Backend30%
Field percentages are editorial estimates of the ticket's engineering focus. They total 100%; they are not measured time, proficiency scores, or ownership evidence.
Review it, then add it to your workspace.
The board opens an editable draft; nothing is saved until you confirm it. Sign-in and workspace permissions apply, and Demo boards remain ephemeral.
Project context
A fictional support platform stores a mutable external account code as its primary relationship key. Renames and imports now break references in several tables.
Setup prerequisites
- Create a disposable database with synthetic customers and dependent records.
- Apply real migration files; never use production db push.
Preceding work
Complete these dependencies, or supply their agreed outputs before taking this ticket.
Acceptance criteria
- Resolve legacy code within organization inside the write boundary.
- Write matching legacy and immutable identity fields together.
- Reject contradictory code/ID pairs.
Implementation constraints
- Do not let controllers bypass the shared repository method.
Verification to include
- Create equivalent cases through old and new local client contracts.
- Supply code for one customer with another ID and verify no row is inserted.
Deliverables
- Compatibility writer and contradiction tests
Rollout and recovery
Deploy bridge writers before enabling new-client reads; revert client routing while retaining dual fields.
Value of the work
For the engineer: Practice migration ordering, compatibility and referential integrity.
For the team: Review a reversible schema transition with measurable completeness checks.
Evidence boundaries
Outcome Evidence: Tests, patches, and runbooks are requested deliverables. They become Outcome Evidence only through a qualified Mission and immutable Evidence IDs.
Ownership Evidence: Independent adaptation must be observed under a declared verification policy and cite immutable Evidence IDs. Completing a planning ticket establishes no Ownership Evidence.