yellowjacket/.planning/milestones/v1.0-phases/07-backend-performance/07-02-SUMMARY.md

phase, plan, subsystem, tags, requires, provides, affects, tech-stack, key-files, key-decisions, patterns-established, requirements-completed, duration, completed

phase	plan	subsystem	tags	requires	provides	affects	tech-stack	key-files	key-decisions	patterns-established	requirements-completed	duration	completed
07-backend-performance	02	ui	performance startup deferred-loading dom-ready wails	phase provides 06-sql-consolidation-code-quality stable frontend store and library data access patterns	Deferred LibraryStore eagerFetch — app shell renders before backend data roundtrips	08-frontend-polish	added patterns deferred-initialization via DOMContentLoaded event	created modified frontend/src/store/library-store.ts	DOMContentLoaded over load event — fires earlier (after HTML parsed) without waiting for all resources, still defers past module evaluation	Deferred singleton initialization: singleton constructors should not fire async work; defer to DOM ready events	PERF-03	1min	2026-03-05

Phase 7 Plan 2: Defer Library Data Loading Summary

Deferred LibraryStore eagerFetch from constructor to DOMContentLoaded event, ensuring app shell renders instantly before 4 backend data roundtrips begin

Performance

• Duration: 1 min
• Started: 2026-03-05T01:53:27Z
• Completed: 2026-03-05T01:54:49Z
• Tasks: 1
• Files modified: 1

Accomplishments

• Removed eagerFetch() call from LibraryStore constructor so module evaluation no longer triggers 4 backend roundtrips
• Added deferEagerFetch() method that waits for DOMContentLoaded event (or calls immediately if DOM already parsed)
• App shell now renders before data fetching competes for resources
• All 4 data types (tracks, albums, artists, genres) still eagerly loaded once DOM is ready
• Post-scan invalidation behavior unchanged — invalidate() still calls eagerFetch() directly

Task Commits

Each task was committed atomically:

1. Task 1: Defer eagerFetch from constructor to post-DOM-ready - cd98ad6 (perf)

Files Created/Modified

• frontend/src/store/library-store.ts - Removed eagerFetch from constructor, added deferEagerFetch with DOMContentLoaded listener

Decisions Made

• Used DOMContentLoaded instead of load event — fires earlier (after HTML parsed, before stylesheets/images finish) which minimizes delay in data availability while still deferring past the initial module evaluation. The load event would unnecessarily wait for all resources before beginning data fetches.

Deviations from Plan

None - plan executed exactly as written.

Issues Encountered

None

User Setup Required

None - no external service configuration required.

Next Phase Readiness

• Plan 02 complete — deferred library loading implemented
• Plan 01 (lazy module loading) may still be pending
• Frontend data loading is now deferred to post-DOM-ready, providing instant app shell render

Self-Check: PASSED

• frontend/src/store/library-store.ts exists
• Commit cd98ad6 exists in git history

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Phase: 07-backend-performance Completed: 2026-03-05