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 | Topic | File | Use |
 |---|---|---|
 | AI excellence due diligence | [ai-excellence-due-diligence-roadmap.md](/home/hartmut/Documents/Copilot/capakraken/docs/ai-excellence-due-diligence-roadmap.md) | Frank quality assessment and cleanup roadmap toward a showcase AI-built project |
+| Showcase quality backlog | [showcase-quality-backlog.md](/home/hartmut/Documents/Copilot/capakraken/docs/showcase-quality-backlog.md) | Consolidated working backlog for the current quality and maintainability north star |
 | Target CI/CD architecture | [cicd-target-architecture.md](/home/hartmut/Documents/Copilot/capakraken/docs/cicd-target-architecture.md) | Canonical image-based build, deploy, and rollback flow |
 | Active roadmap and open gaps | [product-roadmap.md](/home/hartmut/Documents/Copilot/capakraken/docs/product-roadmap.md) | Primary backlog and current delivery order |
 | Estimating system design | [estimating-extension-design.md](/home/hartmut/Documents/Copilot/capakraken/docs/estimating-extension-design.md) | Workbook analysis, field mapping, and implementation plan |
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+# Showcase Quality Backlog
+
+**Date:** 2026-04-01
+**Purpose:** Canonical working backlog for the current north star: turn CapaKraken into a clean, reviewable, deterministic reference project for disciplined AI-assisted software engineering.
+
+## North Star
+
+The goal is not "ship more code at any cost".
+The goal is:
+
+- small ownership surfaces
+- deterministic behavior and repeatable tests
+- explicit permission and runtime boundaries
+- clean deploy and rollback discipline
+- documentation that makes the structure explainable
+- visible engineering quality that holds up under fast AI-assisted change
+
+## Canonical Inputs
+
+This backlog consolidates the still-relevant work from:
+
+- [ai-excellence-due-diligence-roadmap.md](/home/hartmut/Documents/Copilot/capakraken/docs/ai-excellence-due-diligence-roadmap.md)
+- [architecture-hardening-backlog.md](/home/hartmut/Documents/Copilot/capakraken/docs/architecture-hardening-backlog.md)
+- [domain-slices-backlog.md](/home/hartmut/Documents/Copilot/capakraken/docs/domain-slices-backlog.md)
+- [api-router-procedure-support-backlog.md](/home/hartmut/Documents/Copilot/capakraken/docs/api-router-procedure-support-backlog.md)
+
+## Working Rules
+
+- Every touched slice must gain regression coverage for edge, guard, or failure cases, not only happy paths.
+- Prefer narrow, verifiable slices over broad refactors.
+- Keep public contracts stable unless a product decision explicitly changes them.
+- Avoid expanding architecture surface area while the current worktree is dirty or shared ownership is unclear.
+
+## Current Baseline
+
+Already materially improved:
+
+- SSE audience scoping is under CI guardrails.
+- runtime secret handling is environment-first
+- assistant-tool and several router monoliths were decomposed
+- image-based CI/CD and deploy flow exists
+- focused test coverage around several high-risk paths has been expanded
+
+Still open at the quality-showcase level:
+
+- Timeline UX and live-update stability are not yet "boringly reliable".
+- Some large frontend/API ownership surfaces are still too wide.
+- measurable architecture and quality guardrails are not complete yet
+- operational discipline still depends too much on convention and current context
+
+## Priority Stack
+
+### P0. Worktree Hygiene And Deterministic Test Discipline
+
+Status: active, always-on
+
+Done means:
+
+- no generated or accidental artifacts stay tracked
+- shared worktree changes are either validated, isolated, or explicitly left untouched
+- every touched regression suite covers at least one non-happy-path case
+- time- and timezone-sensitive tests are stabilized
+
+Immediate checks:
+
+- keep the current timeline WIP isolated until it is either validated or cleaned
+- continue tightening router/read-model tests where fragile assumptions still exist
+
+### P1. Timeline Interaction, Overlay, And SSE Stability
+
+Status: active
+Source: [domain-slices-backlog.md](/home/hartmut/Documents/Copilot/capakraken/docs/domain-slices-backlog.md)
+
+Remaining work:
+
+- finish popover, hover, drag, and overlay stability across scroll, resize, reload, and view changes
+- verify first-load, reconnect, and live-update behavior under SSE churn
+- close remaining timeline test gaps with explicit edge/failure cases
+- clean up the current timeline component worktree safely before broadening scope
+
+Definition of done:
+
+- timeline popovers and overlays behave consistently under scroll/resize/reload
+- drag and selection interactions do not fight each other
+- SSE reconnects do not leave the UI in a stale or empty state
+
+### P2. Holiday/Vacation Correctness And Explainability Parity
+
+Status: active
+Source: [domain-slices-backlog.md](/home/hartmut/Documents/Copilot/capakraken/docs/domain-slices-backlog.md)
+
+Remaining work:
+
+- close the remaining forecast/widget parity gaps for holiday-/vacation-aware derivations
+- ensure UI, assistant, dashboard detail, and export views expose the same calculation basis
+- keep explainability compact by default and detailed only when explicitly requested
+
+Definition of done:
+
+- the same holiday/vacation logic is visible and test-backed across API, assistant, widgets, and exports
+
+### P3. Resource Read Decomposition And Smaller Ownership Surfaces
+
+Status: next structural cleanup
+Sources:
+
+- [api-router-procedure-support-backlog.md](/home/hartmut/Documents/Copilot/capakraken/docs/api-router-procedure-support-backlog.md)
+- [ai-excellence-due-diligence-roadmap.md](/home/hartmut/Documents/Copilot/capakraken/docs/ai-excellence-due-diligence-roadmap.md)
+
+Remaining work:
+
+- split `resource-read-shared.ts` into focused read helpers without changing public contracts
+- continue shrinking large timeline/frontend modules into easier ownership units
+- keep top-level routers/components thin and orchestration-only
+
+Definition of done:
+
+- the next deep read-model hotspot is decomposed
+- large ownership surfaces become easier to review and test in isolation
+
+### P4. Notification/Task/Broadcast Reliability Residuals
+
+Status: active but below timeline/resource cleanup
+Source: [domain-slices-backlog.md](/home/hartmut/Documents/Copilot/capakraken/docs/domain-slices-backlog.md)
+
+Remaining work:
+
+- close the last persistence and fanout edge cases
+- keep error translation stable and domain-shaped under missing-reference races
+- continue moving complex orchestration toward narrower support helpers where useful
+
+Definition of done:
+
+- reminder, broadcast, and task workflows fail cleanly and predictably under missing-reference and retry scenarios
+
+### P5. Measurable Guardrails In CI
+
+Status: open
+Source: [ai-excellence-due-diligence-roadmap.md](/home/hartmut/Documents/Copilot/capakraken/docs/ai-excellence-due-diligence-roadmap.md)
+
+Remaining work:
+
+- add file-size or ownership-surface guardrails for critical source files
+- add stronger auth/permission regression coverage around sensitive routers
+- add measurable package-level quality gates beyond "tests pass"
+- monitor web bundle or route size where growth risk is known
+
+Definition of done:
+
+- CI can fail for structural regressions, not only syntax or unit failures
+
+### P6. Operational Standardization
+
+Status: open
+Source: [ai-excellence-due-diligence-roadmap.md](/home/hartmut/Documents/Copilot/capakraken/docs/ai-excellence-due-diligence-roadmap.md)
+
+Remaining work:
+
+- make Redis-backed rate limiting an intentional deployed default, not a best-effort fallback
+- document and rehearse one rollback path
+- finish deploy/bootstrap/cleanup discipline around runtime secrets and environment-backed config
+
+Definition of done:
+
+- one production path, one rollback path, one runtime config source of truth
+
+### P7. Reference-Project Artifacts
+
+Status: open
+Source: [ai-excellence-due-diligence-roadmap.md](/home/hartmut/Documents/Copilot/capakraken/docs/ai-excellence-due-diligence-roadmap.md)
+
+Remaining work:
+
+- add an engineering doctrine for AI-assisted changes
+- add explicit AI collaboration standards for file growth, tests, and docs
+- curate a small set of exemplary slices that demonstrate the intended standards end to end
+
+Suggested artifacts:
+
+- `docs/engineering-doctrine.md`
+- `docs/ai-collaboration-standards.md`
+- reference-slice documentation for one API slice and one frontend slice
+
+## Practical Order From Here
+
+If the goal is to keep momentum without widening risk, the recommended execution order is:
+
+1. finish or safely isolate the current Timeline worktree changes
+2. continue non-happy-path coverage on touched timeline/resource reads
+3. complete the remaining holiday/vacation parity gaps
+4. decompose `resource-read-shared.ts`
+5. return to residual notification reliability edges
+6. add the next CI guardrail instead of another broad refactor
+
+## Exit Criteria For This Backlog
+
+This backlog is complete when:
+
+- the main UX-critical surfaces are stable under edge conditions
+- the next major oversized ownership surfaces are reduced
+- quality is enforced by CI guardrails, not memory
+- operations are repeatable and documented
+- the repository visibly demonstrates disciplined AI-assisted engineering rather than just fast iteration