From 8f8af48a12d8c453b343d2488b82d7d25bac5bc2 Mon Sep 17 00:00:00 2001 From: Caleb Allen Date: Mon, 16 Mar 2026 16:08:19 -0400 Subject: [PATCH] docs: update retrospective for v1.1 --- .planning/RETROSPECTIVE.md | 59 +++++++++++++++++++++++++++++++++++++- 1 file changed, 58 insertions(+), 1 deletion(-) diff --git a/.planning/RETROSPECTIVE.md b/.planning/RETROSPECTIVE.md index 6bb8961..e40e632 100644 --- a/.planning/RETROSPECTIVE.md +++ b/.planning/RETROSPECTIVE.md @@ -55,6 +55,59 @@ --- +## Milestone: v1.1 — Multi-Library Support + +**Shipped:** 2026-03-16 +**Phases:** 6 | **Plans:** 18 +**Timeline:** 10 days (2026-03-06 → 2026-03-16) + +### What Was Built +- Cancellable/pausable library scans with per-scan context cancellation and sequential queue coordination +- Configurable keyboard shortcuts with record-style capture UI, scope-aware dispatch, and conflict detection +- Multi-library database schema (migration 6) with seamless single-directory migration +- Per-library scan pipeline with scan queue, per-library progress UI, and cancel scope +- Full library CRUD API with 17-step atomic removal (orphan cleanup, phantom metadata, FTS5, cover art, queue compaction) +- Library filter dropdown — all views (tracks, albums, artists, genres, search) respect active filter +- Cross-library playlists with phantom track auto-resolution via ScanHooks + M3U8 path matching +- Performance: CSS containment, view caching, event delegation, content-visibility, scroll polish + +### What Worked +- **4-phase multi-library progression (schema → scan → CRUD → views):** Each phase had clear boundaries and verifiable outputs. Schema first meant scan pipeline had stable types; scan pipeline meant CRUD had working add-then-scan; CRUD meant views could demonstrate the full lifecycle. +- **Locked decisions from /gsd-discuss-phase:** "Backend filtering, not frontend" and "SET NULL for playlist_tracks FK" were decided once and never revisited — eliminated mid-execution design debates. +- **Performance phase running in parallel:** Phase 14 (performance) was independent of the multi-library phases (10-13), allowing it to execute when multi-library phases were blocked on human verification. +- **Checkpoint-driven bugfinding:** The human-verify checkpoint in Phase 13 found 3 bugs (virtualizer event delegation race, missing phantom auto-resolution, M3U8-based resolution needed) that wouldn't have been caught by automated verification alone. +- **Hook patterns for cross-package communication:** ScanHooks, RemovalHooks, and RescanHooks cleanly broke circular dependencies between library, playlist, and queue packages without coupling. + +### What Was Inefficient +- **Phantom resolution required 3 iterations:** First attempt (pure SQL with phantom_file_path) missed pre-existing phantoms. Second attempt (backfill) was fragile. Third attempt (M3U8-based ScanHooks) was the right approach from the start. Should have analyzed the M3U8 data flow before designing the resolution. +- **Phase 14 virtualizer bug surfaced late:** The event delegation race condition from Phase 14-03 wasn't caught until Phase 13's checkpoint. The Phase 14 verification should have included testing with empty-then-loaded data states. +- **Quick task 19 (phantom path resolution) overlapped with Phase 13:** The fix for multi-root path resolution in playlists was done as a quick task but directly related to Phase 13's phantom track work. Could have been folded into Phase 13 planning. + +### Patterns Established +- **ScanHooks callback pattern:** Post-scan processing without circular imports — library calls hook, playlist implements +- **ByLibrary query variants:** Parallel filtered/unfiltered sqlc queries with conditional dispatch in store layer +- **phantom_file_path column:** Preserves original file path at removal time for future re-linking +- **M3U8 as source of truth for phantom matching:** Position-based + path-based dual matching strategy +- **View caching with display:none toggle:** Keeps DOM alive for instant navigation, bounded cache (6 entries) +- **Event delegation via data-index + closest():** Zero per-item closures in virtualizer renderItem functions +- **attachDelegation guard pattern:** Retry event delegation in updated() for conditionally-rendered elements +- **changeGeneration counter:** Simple monotonic counter replaces typed subscription system for store change detection + +### Key Lessons +1. **Analyze data flow before designing resolution strategies:** The phantom track resolution should have started with "what data do we have?" (M3U8 files have the paths) rather than "where can we store new data?" (phantom_file_path column). The M3U8 approach was simpler and more robust. +2. **Human checkpoints catch integration bugs that automated tests miss:** The virtualizer race condition and phantom auto-resolution gap were both found during manual testing, not by build/lint/verify. Budget for checkpoint time. +3. **Hook patterns scale well for cross-cutting concerns:** ScanHooks, RemovalHooks, and RescanHooks all follow the same pattern — define struct with function fields, set via method, call at lifecycle points. This pattern can be reused for future cross-package coordination. +4. **Conditional rendering + lifecycle hooks need careful testing:** Components that conditionally render children (lit-virtualizer appears only when data loads) must handle the case where firstUpdated fires before the child exists. Test with both fast and slow data loading. +5. **Performance optimization and feature work can truly run in parallel:** Phase 14 had zero file conflicts with Phases 10-13 and was executed out of order. Independent subsystem identification at planning time enables this parallelism. + +### Cost Observations +- Model mix: Primarily opus for planning + execution, sonnet for verification +- Total commits: ~85 across 10 days +- Notable: Most plans completed in 2-10 minutes. Phase 12-02 (frontend library management UI) was the longest at 38 minutes due to complexity (19 files, 3 tasks, new components) +- Efficiency: 18 plans across 6 phases with 4 quick tasks interleaved + +--- + ## Cross-Milestone Trends ### Process Evolution @@ -62,15 +115,19 @@ | Milestone | Days | Phases | Plans | Key Change | |-----------|------|--------|-------|------------| | v1.0 | 6 | 8 | 17 | First milestone — established GSD workflow, research-before-plan pattern | +| v1.1 | 10 | 6 | 18 | Locked decisions, parallel phase execution, hook patterns for cross-package coordination | ### Cumulative Quality | Milestone | Tests Added | Total Tests | Key Quality Win | |-----------|-------------|-------------|-----------------| | v1.0 | 84 | 84 | From 0 backend tests to comprehensive coverage of queue, config, player, database, library | +| v1.1 | ~5 | ~89 | Migration tests, multi-root path resolution tests; human checkpoint caught 3 integration bugs | ### Top Lessons (Verified Across Milestones) -1. Dependency-ordered phases (fix → test → refactor → optimize) prevent rework and ensure each phase builds on a stable foundation +1. Dependency-ordered phases (fix → test → refactor → optimize; schema → scan → CRUD → views) prevent rework and ensure each phase builds on a stable foundation 2. Small plans (2-3 tasks, <10 min) maintain consistent quality — no context degradation 3. Research phases for unfamiliar domains (sqlc + VIEW, lit-virtualizer API) prevent mid-execution surprises +4. Human checkpoints catch integration bugs that automated verification misses — budget time for them +5. Analyze existing data flows before designing new storage — the simplest solution often uses data that already exists