# Implementation Plan: Multi-Tenant SaaS Platform for Malaysian SMEs

**Branch**: `001-1-target-sectors` | **Date**: 2025-10-04 | **Spec**: /specs/001-1-target-sectors/spec.md
**Input**: Feature specification from `/specs/001-1-target-sectors/spec.md`

## Execution Flow (/plan command scope)
```
1. Load feature spec from Input path
   → If not found: ERROR "No feature spec at {path}"
2. Fill Technical Context (scan for NEEDS CLARIFICATION)
   → Detect Project Type from file system structure or context (web=frontend+backend, mobile=app+api)
   → Set Structure Decision based on project type
3. Fill the Constitution Check section based on the content of the constitution document.
4. Evaluate Constitution Check section below
   → If violations exist: Document in Complexity Tracking
   → If no justification possible: ERROR "Simplify approach first"
   → Update Progress Tracking: Initial Constitution Check
5. Execute Phase 0 → research.md
   → If NEEDS CLARIFICATION remain: ERROR "Resolve unknowns"
6. Execute Phase 1 → contracts, data-model.md, quickstart.md, agent-specific template file (e.g., `CLAUDE.md` for Claude Code, `.github/copilot-instructions.md` for GitHub Copilot, `GEMINI.md` for Gemini CLI, `QWEN.md` for Qwen Code, or `AGENTS.md` for all other agents).
7. Re-evaluate Constitution Check section
   → If new violations: Refactor design, return to Phase 1
   → Update Progress Tracking: Post-Design Constitution Check
8. Plan Phase 2 → Describe task generation approach (DO NOT create tasks.md)
9. STOP - Ready for /tasks command
```

**IMPORTANT**: The /plan command STOPS at step 7. Phases 2-4 are executed by other commands:
- Phase 2: /tasks command creates tasks.md
- Phase 3-4: Implementation execution (manual or via tools)

## Summary
Multi-tenant SaaS platform targeting Malaysian SMEs with industry-specific modules (Retail, Healthcare, Education, Logistics, Beauty). Features include modular architecture, dual pricing models (subscription and perpetual license), multi-tenant data isolation, and comprehensive business management tools for each sector.

## Technical Context
**Language/Version**: Python 3.11+ with Django/FastAPI for backend, React/Next.js for frontend
**Primary Dependencies**: Django/FastAPI, PostgreSQL, React/Next.js, Stripe API, Redis, Docker
**Storage**: PostgreSQL with row-level security for multi-tenant isolation
**Testing**: pytest for backend, Jest for frontend, integration tests for APIs
**Target Platform**: Web-based SaaS platform (Linux servers)
**Project Type**: Web application (backend + frontend)
**Performance Goals**: 1000 concurrent users, <200ms response time for 95% of requests
**Constraints**: Multi-tenant data isolation, Malaysian payment method integration, healthcare compliance standards
**Scale/Scope**: 100 tenants with 10 users each (expandable), 5 industry modules

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

**Constitution Status**: Template placeholders detected - actual constitution needs to be defined
- Core principles not yet defined
- Testing approach needs constitutional alignment
- Governance structure requires specification

**Recommendation**: Define constitution before proceeding with implementation to ensure alignment with project values and standards.

## Project Structure

### Documentation (this feature)
```
specs/001-1-target-sectors/
├── plan.md              # This file (/plan command output)
├── research.md          # Phase 0 output (/plan command)
├── data-model.md        # Phase 1 output (/plan command)
├── quickstart.md        # Phase 1 output (/plan command)
├── contracts/           # Phase 1 output (/plan command)
└── tasks.md             # Phase 2 output (/tasks command - NOT created by /plan)
```

### Source Code (repository root)
```
backend/
├── src/
│   ├── core/                 # Core multi-tenant infrastructure
│   │   ├── models/          # Base tenant, user, subscription models
│   │   ├── auth/            # Authentication and authorization
│   │   ├── billing/         # Subscription and payment handling
│   │   └── admin/           # Back office administration
│   ├── modules/             # Industry-specific modules
│   │   ├── retail/          # Retail & Food Stalls module
│   │   ├── healthcare/      # Healthcare module
│   │   ├── education/      # Education module
│   │   ├── logistics/       # Logistics module
│   │   └── beauty/          # Beauty & Personal Care module
│   └── api/                # REST API endpoints
├── tests/
│   ├── contract/            # API contract tests
│   ├── integration/         # Module integration tests
│   └── unit/               # Unit tests
└── migrations/             # Database migrations

frontend/
├── src/
│   ├── components/         # Reusable UI components
│   ├── pages/              # Application pages
│   ├── modules/            # Module-specific components
│   ├── hooks/              # Custom React hooks
│   ├── services/           # API service layer
│   └── utils/              # Utility functions
├── tests/                  # Frontend tests
└── public/                 # Static assets

shared/
├── types/                  # TypeScript type definitions
└── contracts/             # Shared API contracts

docker/                     # Docker configuration
├── backend/
├── frontend/
└── postgres/

docs/                       # Project documentation
└── api/                    # API documentation
```

**Structure Decision**: Web application with separate backend/frontend for scalability and independent deployment. Modular backend structure allows for plug-and-play industry modules. Shared types ensure API consistency.

## Progress Tracking
- [x] Phase 0: Research completed (research.md generated)
- [x] Phase 1: Design completed (data-model.md, contracts/, quickstart.md generated)
- [x] Phase 2: Task planning (122 tasks created in tasks.md)
- [ ] Phase 3: Task execution (ready to begin)
- [ ] Phase 4: Implementation (pending)
- [ ] Phase 5: Validation (pending)

## Phase 0: Outline & Research
1. **Extract unknowns from Technical Context** above:
   - For each NEEDS CLARIFICATION → research task
   - For each dependency → best practices task
   - For each integration → patterns task

2. **Generate and dispatch research agents**:
   ```
   For each unknown in Technical Context:
     Task: "Research {unknown} for {feature context}"
   For each technology choice:
     Task: "Find best practices for {tech} in {domain}"
   ```

3. **Consolidate findings** in `research.md` using format:
   - Decision: [what was chosen]
   - Rationale: [why chosen]
   - Alternatives considered: [what else evaluated]

**Output**: research.md with all NEEDS CLARIFICATION resolved

## Phase 1: Design & Contracts
*Prerequisites: research.md complete*

1. **Extract entities from feature spec** → `data-model.md`:
   - Entity name, fields, relationships
   - Validation rules from requirements
   - State transitions if applicable

2. **Generate API contracts** from functional requirements:
   - For each user action → endpoint
   - Use standard REST/GraphQL patterns
   - Output OpenAPI/GraphQL schema to `/contracts/`

3. **Generate contract tests** from contracts:
   - One test file per endpoint
   - Assert request/response schemas
   - Tests must fail (no implementation yet)

4. **Extract test scenarios** from user stories:
   - Each story → integration test scenario
   - Quickstart test = story validation steps

5. **Update agent file incrementally** (O(1) operation):
   - Run `.specify/scripts/bash/update-agent-context.sh claude`
     **IMPORTANT**: Execute it exactly as specified above. Do not add or remove any arguments.
   - If exists: Add only NEW tech from current plan
   - Preserve manual additions between markers
   - Update recent changes (keep last 3)
   - Keep under 150 lines for token efficiency
   - Output to repository root

**Output**: data-model.md, /contracts/*, failing tests, quickstart.md, agent-specific file

## Phase 2: Task Planning Approach
*This section describes what the /tasks command will do - DO NOT execute during /plan*

**Task Generation Strategy**:
- Load `.specify/templates/tasks-template.md` as base
- Generate tasks from Phase 1 design docs (contracts, data model, quickstart)
- Each contract → contract test task [P]
- Each entity → model creation task [P] 
- Each user story → integration test task
- Implementation tasks to make tests pass

**Ordering Strategy**:
- TDD order: Tests before implementation 
- Dependency order: Models before services before UI
- Mark [P] for parallel execution (independent files)

**Estimated Output**: 25-30 numbered, ordered tasks in tasks.md

**IMPORTANT**: This phase is executed by the /tasks command, NOT by /plan

## Phase 3+: Future Implementation
*These phases are beyond the scope of the /plan command*

**Phase 3**: Task execution (/tasks command creates tasks.md)  
**Phase 4**: Implementation (execute tasks.md following constitutional principles)  
**Phase 5**: Validation (run tests, execute quickstart.md, performance validation)

## 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] |


## Progress Tracking
*This checklist is updated during execution flow*

**Phase Status**:
- [ ] Phase 0: Research complete (/plan command)
- [ ] Phase 1: Design complete (/plan command)
- [ ] Phase 2: Task planning complete (/plan command - describe approach only)
- [ ] Phase 3: Tasks generated (/tasks command)
- [ ] Phase 4: Implementation complete
- [ ] Phase 5: Validation passed

**Gate Status**:
- [ ] Initial Constitution Check: PASS
- [ ] Post-Design Constitution Check: PASS
- [ ] All NEEDS CLARIFICATION resolved
- [ ] Complexity deviations documented

---
*Based on Constitution v2.1.1 - See `/memory/constitution.md`*