---
phase: 05-hardening-and-docs
plan: "02"
subsystem: documentation
tags: [maintainer-docs, developer-guide, architecture-overview, onboarding]

# Dependency graph
requires:
  - phase: 05-hardening-and-docs
    provides: "Fuzz targets, Justfile recipes, NightlyFuzz CI workflow (from plan 05-01)"
  - phase: 01-scaffold
    provides: "CI workflows (PullRequestCI, MainDistributionPipeline, CodeQuality, DuckDBVersionMonitor)"
  - phase: 02-storage-and-ddl
    provides: "DDL functions (define, drop, list, describe) and catalog persistence"
  - phase: 03-expansion-engine
    provides: "expand() SQL generation engine"
  - phase: 04-query-interface
    provides: "semantic_query and explain_semantic_view table functions"
provides:
  - "Complete MAINTAINER.md covering 12 sections of the developer lifecycle"
  - "Architecture overview mapping every src/ file to its conceptual role"
  - "Two worked examples: adding a DDL function, adding a metric type"
  - "Troubleshooting guide for 5 common errors with root-cause explanations"
affects: []

# Tech tracking
tech-stack:
  added: []
  patterns: [python-audience-first-docs, rust-concept-footnotes]

key-files:
  created:
    - MAINTAINER.md
  modified: []

key-decisions:
  - "python-audience-first-tone: All Rust concepts explained with Python analogies as inline footnotes, not standalone sections"
  - "single-source-doc: MAINTAINER.md is self-contained with no 'see also' chains for essential workflows"
  - "feature-flag-explainer: Dedicated subsection explaining bundled vs extension feature split since it is the #1 source of confusion"

patterns-established:
  - "Documentation tone: Python analogies for Rust concepts (Cargo.toml = pyproject.toml, rustup = pyenv)"
  - "Worked examples pattern: step-by-step with file paths, code snippets, and registration instructions"

requirements-completed: [DOCS-01]

# Metrics
duration: 3min
completed: 2026-02-26
---

# Phase 5 Plan 02: MAINTAINER.md Summary

**Comprehensive MAINTAINER.md covering 12 developer lifecycle sections with Python-first tone, architecture source tree map, two worked examples, and troubleshooting for 5 common errors**

## Performance

- **Duration:** 3 min
- **Started:** 2026-02-26T11:09:34Z
- **Completed:** 2026-02-26T11:12:58Z
- **Tasks:** 1
- **Files modified:** 1

## Accomplishments
- Created 687-line MAINTAINER.md at project root covering the complete developer lifecycle
- Architecture overview maps every file in src/ (13 files across lib, model, catalog, expand, ddl/, query/) to its conceptual role with data flow explanation
- Two worked examples (adding a DDL function, adding a metric type) with step-by-step file changes and registration instructions
- Troubleshooting section covers 5 common errors with root-cause "why" explanations, not just fix commands
- Python-first audience: Rust concepts explained as footnotes with analogies (rustup=pyenv, Cargo.toml=pyproject.toml, features=extras_require)

## Task Commits

Each task was committed atomically:

1. **Task 1: Write MAINTAINER.md with all required sections, architecture overview, and worked examples** - `c99fde9` (feat)

## Files Created/Modified
- `MAINTAINER.md` - Complete maintainer documentation covering all 12 required sections

## Decisions Made
- **Python-audience-first tone:** All Rust concepts explained with Python analogies as inline footnotes rather than standalone Rust tutorial sections
- **Single-source document:** MAINTAINER.md is self-contained -- no "see also" chains to external docs for any essential workflow
- **Feature flag explainer:** Dedicated subsection explaining the `bundled` vs `extension` feature split since it is the most common source of confusion for new contributors

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered

None.

## User Setup Required

None - no external service configuration required.

## Next Phase Readiness
- All Phase 5 plans complete (fuzz targets + MAINTAINER.md)
- All v0.1 requirements satisfied (INFRA-01..04, STYLE-01..02, DDL-01..05, MODEL-01..04, EXPAND-01..04, TEST-01..05, QUERY-01..04, DOCS-01)
- The project is ready for community extension registry publishing

## Self-Check: PASSED

All 1 created file verified present. Task commit (c99fde9) verified in git log.

---
*Phase: 05-hardening-and-docs*
*Completed: 2026-02-26*
