# Implementation Plan: [FEATURE]

**Branch**: `[###-feature-name]` | **Date**: [DATE] | **Spec**: [link]
**Input**: Feature specification from `/specs/[###-feature-name]/spec.md`

**Note**: This template is filled in by the `/speckit.plan` command. See `.specify/templates/commands/plan.md` for the execution workflow.

## Summary

[Extract from feature spec: primary requirement + technical approach from research]

## Technical Context

<!--
  ACTION REQUIRED: Replace the content in this section with the technical details
  for the project. The structure here is presented in advisory capacity to guide
  the iteration process.
-->

**Language/Version**: [e.g., Python 3.11, Swift 5.9, Rust 1.75 or NEEDS CLARIFICATION]
**Primary Dependencies**: [e.g., FastAPI, UIKit, LLVM or NEEDS CLARIFICATION]
**Storage**: [if applicable, e.g., PostgreSQL, CoreData, files or N/A]
**Testing**: [e.g., pytest, XCTest, cargo test or NEEDS CLARIFICATION]
**Target Platform**: [e.g., Linux server, iOS 15+, WASM or NEEDS CLARIFICATION]
**Project Type**: [single/web/mobile - determines source structure]
**Performance Goals**: [domain-specific, e.g., 1000 req/s, 10k lines/sec, 60 fps or NEEDS CLARIFICATION]
**Constraints**: [domain-specific, e.g., <200ms p95, <100MB memory, offline-capable or NEEDS CLARIFICATION]
**Scale/Scope**: [domain-specific, e.g., 10k users, 1M LOC, 50 screens or NEEDS CLARIFICATION]

## Constitution Check

*GATE: Must pass before Phase 0 research. Re-check after Phase 1 design.*

The following principles from `.specify/memory/constitution.md` MUST be verified:

### I. Test-Driven Development (NON-NEGOTIABLE)
- [ ] Tests planned before implementation
- [ ] Red-Green-Refactor cycle documented in tasks
- [ ] Test coverage targets defined (>80% general, 100% critical paths)

### II. API-First Design
- [ ] API contracts documented with Pydantic schemas
- [ ] Request/response formats specified
- [ ] Error handling and status codes defined
- [ ] Authentication/authorization requirements documented

### III. Asynchronous Architecture
- [ ] I/O-bound operations use async patterns
- [ ] Background tasks delegated to Celery (if applicable)
- [ ] Database operations use async drivers
- [ ] Caching strategy defined (if applicable)

### IV. Observability and Monitoring
- [ ] Logging strategy defined with structured logs
- [ ] Tracing instrumentation planned (OpenTelemetry)
- [ ] Metrics collection specified
- [ ] Error tracking approach documented

### V. Type Safety and Validation
- [ ] Pydantic models defined for all data structures
- [ ] Type hints planned for all functions
- [ ] Input validation at API boundaries
- [ ] Runtime validation strategy specified

### VI. Security by Default
- [ ] No credentials in code (environment variables only)
- [ ] Input validation and sanitization planned
- [ ] Authentication/authorization requirements clear
- [ ] SQL injection prevention via parameterized queries
- [ ] Security audit plan included

**PASS CRITERIA**: All checkboxes must be checked or explicitly waived with justification in Complexity Tracking section.

## Project Structure

### Documentation (this feature)

```text
specs/[###-feature]/
├── plan.md              # This file (/speckit.plan command output)
├── research.md          # Phase 0 output (/speckit.plan command)
├── data-model.md        # Phase 1 output (/speckit.plan command)
├── quickstart.md        # Phase 1 output (/speckit.plan command)
├── contracts/           # Phase 1 output (/speckit.plan command)
└── tasks.md             # Phase 2 output (/speckit.tasks command - NOT created by /speckit.plan)
```

### Source Code (repository root)
<!--
  ACTION REQUIRED: Replace the placeholder tree below with the concrete layout
  for this feature. Delete unused options and expand the chosen structure with
  real paths (e.g., apps/admin, packages/something). The delivered plan must
  not include Option labels.
-->

```text
# [REMOVE IF UNUSED] Option 1: Single project (DEFAULT)
src/
├── models/
├── services/
├── cli/
└── lib/

tests/
├── contract/
├── integration/
└── unit/

# [REMOVE IF UNUSED] Option 2: Web application (when "frontend" + "backend" detected)
backend/
├── src/
│   ├── models/
│   ├── services/
│   └── api/
└── tests/

frontend/
├── src/
│   ├── components/
│   ├── pages/
│   └── services/
└── tests/

# [REMOVE IF UNUSED] Option 3: Mobile + API (when "iOS/Android" detected)
api/
└── [same as backend above]

ios/ or android/
└── [platform-specific structure: feature modules, UI flows, platform tests]
```

**Structure Decision**: [Document the selected structure and reference the real
directories captured above]

## Complexity Tracking

> **Fill ONLY if Constitution Check has violations that must be justified**

| Violation | Why Needed | Simpler Alternative Rejected Because |
|-----------|------------|-------------------------------------|
| [e.g., 4th project] | [current need] | [why 3 projects insufficient] |
| [e.g., Repository pattern] | [specific problem] | [why direct DB access insufficient] |