Phase D. Depends on the [#607678](https://gitlab.com/gitlab-org/gitlab/-/work_items/607678) data migration having run. ## Problem Closes the last acceptance criterion on [#603494](https://gitlab.com/gitlab-org/gitlab/-/work_items/603494): *"The bespoke trigger code introduced in &20711 is removed or replaced."* ## Implementation — complete inventory (verified) ### ⚠️ Ordering trap Removing `dap_powered: 2` from the enum deletes the generated predicate `reviewer_assignment_dap_powered?`. `AutoAssignReviewersWorker#perform` calls it unconditionally at line 23, so **the enum value and the worker branch must be removed in the same commit** — otherwise every worker invocation (including plain `code_owners` projects) raises `NoMethodError`. ### Deletions - `ee/app/workers/merge_requests/auto_assign_reviewers_worker.rb` — the `reviewer_assignment_dap_powered?` branch (line 23-25), `execute_dap_flow` + its internal event + warn logging (lines 36-59). The `else` body (AssignService call) becomes the only path. Spec: delete the `dap_powered` context block (`auto_assign_reviewers_worker_spec.rb:105-190`). - `ee/app/services/ai/duo_workflows/recommend_reviewers/execute_service.rb` — delete (the worker is the only production caller); delete `execute_service_spec.rb`. - `ee/app/models/ee/project.rb:736-744` — delete `dap_powered_recommend_reviewers_available?`; delete its spec block (`ee/spec/models/ee/project_spec.rb:6327-6380`). - `app/models/project_setting.rb:25` — remove `dap_powered: 2` from `REVIEWER_ASSIGNMENT_STRATEGIES` (one-line CE change; the EE concern doesn't touch the enum). - `ee/config/feature_flags/wip/dap_powered_recommend_reviewers.yml` — remove; record the outcome of [#607676](https://gitlab.com/gitlab-org/gitlab/-/work_items/607676) here (any catalog gate is a separate, fresh flag). - Fold in the deprecated no-op worker removal ([#602537](https://gitlab.com/gitlab-org/gitlab/-/work_items/602537)) — exactly four references: `ee/app/workers/merge_requests/execute_merge_request_ready_worker.rb`, `ee/app/workers/all_queues.yml:3367-3376`, `config/sidekiq_queues.yml:740`, `ee/spec/workers/merge_requests/execute_merge_request_ready_worker_spec.rb`. It is not subscribed anywhere. (Do not confuse with the `ai_catalog_flows_execute_merge_request_ready_workflow_triggers` queue — that's the replacement.) ### Keep — verified still needed - `Ai::DuoWorkflows::RecommendReviewers::ReviewerDataBuilder` — its only production caller is the `additional_context_resolver` on the `recommend_reviewers/v1` item (`items.rb:203`), which **is** the trigger path after [#607673](https://gitlab.com/gitlab-org/gitlab/-/work_items/607673). - The `recommend_reviewers/v1` catalog item itself (`items.rb:186-206`) and its pot strings — it's the product now. - `PendingInitialAssignment` + the EE `ReloadMergeHeadDiffService` enqueue and the draft→ready enqueue in `EE::MergeRequests::UpdateService` — still serve the `code_owners` strategy. Note the EE `ReloadMergeHeadDiffService` override also owns `sync_code_owner_approval_rules`; it is not reviewer-assignment-only machinery. - The `auto_assign_reviewers` internal event definition (`ee/config/events/auto_assign_reviewers.yml`) — still fired by `AssignService` with `label: 'code_owners'`, and its `label` description ("The assignment strategy used") stays accurate. - The `project_settings.reviewer_assignment_strategy` column. - Stale rows with value `2` (if any escaped Phase C) degrade gracefully: unmapped enum reads as `nil`, `StrategyFactory.build` returns `nil`, `AssignService` skips with `'No strategy available'` — no crash (verified against Rails 7.2 enum deserialize; covered by `strategy_factory_spec.rb:32-40`). ### Measurement continuity — resolved There are **no metric definitions** consuming `auto_assign_reviewers` (nothing in `config/metrics/` or `ee/config/metrics/`), so deleting the worker's `label: 'dap_powered'` event call breaks no dashboard. Trigger-driven runs are already measured by the `trigger_ai_catalog_item` internal event emitted per run with the catalog item id, event type, and item properties (`run_service.rb:443-459`, granular since `6d643e58d193`). Record in the rollout notes that DAP reviewer-assignment adoption is thereafter read from `trigger_ai_catalog_item` filtered to the Recommend Reviewers item, replacing `auto_assign_reviewers[label=dap_powered]`. ### Optional adjacent cleanup `app/models/project_setting.rb:42` carries `ignore_column :code_owner_reviewer_assignment_strategy, remove_with: '19.0', remove_after: '2026-04-22'` — past its remove-after date; can ride along. ## Acceptance criteria - [ ] No references to `dap_powered` remain outside the Phase C migration - [ ] Enum value and worker branch removed in the same commit (no `NoMethodError` window) - [ ] `ReviewerDataBuilder` still reachable from the trigger path - [ ] `code_owners` strategy behaviour unchanged - [ ] Measurement hand-off recorded: `trigger_ai_catalog_item` (Recommend Reviewers item) replaces `auto_assign_reviewers[label=dap_powered]` - [ ] `MergeRequests::ExecuteMergeRequestReadyWorker` no-op removed ([#602537](https://gitlab.com/gitlab-org/gitlab/-/work_items/602537))