Development

This section covers everything needed to contribute to DiveSuite: setup, standards, testing, and CI/CD.

Quick Start

# Prerequisites
node --version  # v22+ (see .nvmrc)
rustup --version  # Rust toolchain for deco engine

# Clone and setup
git clone https://github.com/DiveSuite/app.git
cd DiveSuite

# Install dependencies (once Expo project exists)
npm install

# Start development
npx expo start

Project Structure

DiveSuite/
├── app/                    # Expo Router file-based routes
├── src/
│   ├── core/               # Shared core (no UI dependency)
│   │   ├── engine/         # Rust/WASM bridge
│   │   ├── database/       # WatermelonDB
│   │   ├── models/         # Domain types
│   │   ├── services/       # Business logic
│   │   ├── i18n/           # Internationalization
│   │   └── utils/          # Pure utilities
│   ├── features/           # Feature modules
│   │   ├── planning/       # {screens, components, hooks}
│   │   ├── logging/
│   │   ├── analysis/
│   │   ├── community/
│   │   ├── settings/
│   │   └── ai/
│   └── shared/             # Shared UI
│       ├── components/
│       ├── theme/
│       ├── hooks/
│       └── navigation/
├── rust-engine/            # Rust deco engine
├── docs-site/              # MkDocs documentation
├── planning/               # Planning documents
└── architecture/           # Architecture documents

Documents

Document	Description
Getting Started	Environment setup, first run
Project Structure	Folder organization (AD-10)
Coding Standards	TypeScript, Rust, naming conventions
Testing Strategy	Test pyramid, coverage targets, safety tests
CI/CD	GitHub Actions, quality gates, deployment
MCP Setup	Model Context Protocol servers for AI-assisted development

Key Standards

File Size Limits

File Type	Max Lines
Screen component	250
UI component	150
Custom hook	100
Service class	300
Rust module	400

Code Quality

Metric	Limit
Line length	100 chars
Function body	30 lines
Function parameters	4 max
Nesting depth	3 levels

Coverage Targets

Code	Target
Deco Engine (Rust)	95%+ branch coverage
Core Services (TS)	80%+ line coverage
UI Components	Behavior tests only

Git Workflow

Branch model: Trunk-based with short-lived feature branches
Commits: Conventional Commits (feat:, fix:, refactor:, etc.)
Branches: feature/E{milestone}.{epic}-description
Merges: Squash-merge only, auto-delete branches

Safety Rules