Claude Code Guidelines for OilField Project

# Claude Code Guidelines for OilField Project

## Task Execution Strategy

### Context Optimization
Extensively use tasks and subtasks (Task tool) to optimize the context usage.

### Parallel Execution
Extensively use parallel tasks and subtasks (multiple Task tools running in the same message) to make the work be done much faster.

### Map-Reduce Approach
Use map-reduce approach with parallel tasks and subtasks.

### Task Reporting
Ensure each task or subtask reports back a very brief explanation on what was done, and what still needs to be done (if any).

### Problem Resolution
Ensure that in case of any problem that task or subtask experiences, it **must** spawn another [set of] subtask(s) to do necessary research and/or experiments in order to resolve the issue.

### Planning and Tracking
Extensively use planning (with TodoWrite tool), so all work is being thoroughly and reliably tracked, and nothing is skipped or lost.

### Parallelization Limits
The maximum number of tasks or subtasks running in parallel should not be more than CPU cores on this machine.

## Software Engineering Principles

### SOLID Principles
You must religiously follow SOLID principles:
- **S**ingle Responsibility Principle
- **O**pen/Closed Principle
- **L**iskov Substitution Principle
- **I**nterface Segregation Principle
- **D**ependency Inversion Principle

### Additional Principles
- **KISS** (Keep It Simple, Stupid)
- **DRY** (Don't Repeat Yourself)
- **YAGNI** (You Aren't Gonna Need It)
- **TRIZ** (Theory of Inventive Problem Solving)

## Development Process

### Test-Driven Development (TDD)
You must religiously follow TDD (Test-Driven Development) process:
1. Write failing test first
2. Write minimal code to pass
3. Refactor while keeping tests green

### Testing Requirements
You must create both unit tests and integration tests.

### Type Safety
You must do the code as strongly-typed as possible, and even more, so we can find errors **before** we run code in production.

### Linting
You **must** extensively and exhaustively run applicable linters every time before sending code to github.

### Code Review
You must review the changes made with a separate subtask.

## Git Workflow

### Git Flow
You **must** use git flow for all git/github-related actions (if applicable).

### No Pull Requests
No Pull Requests - I am solo here.

### Commit and Push
You **must** commit and push code every time when you are done with any engineering task.

### Releases
You **must** do git release after each significant feature or piece is implemented.

## Database Management

### Schema Preservation
If the database is in place with correct schema, you **must NOT** touch that schema again. Do not run migrations or alter existing tables unless explicitly requested.

### Data Preservation
If the data is already in the database, you **must NOT** modify, delete, or re-insert it unless explicitly requested. Do not run seed scripts, data population scripts, or any operations that would alter existing data. Always verify what data exists before attempting any data operations.

### Database Connection Information
The project uses PostgreSQL with the following connection details:
- **Host**: localhost
- **Port**: 5434
- **Database**: oilfield
- **User**: oilfield
- **Password**: oilfield_dev
- **Connection URL**: postgresql://oilfield:oilfield_dev@localhost:5434/oilfield

Configuration files:
- Root: `.env` (active configuration)
- Backend: `backend/.env` (uses port 5432)
- Examples: `.env.example` and `backend/.env.example`