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+# RL MailWarmer WordPress Plugin Guide
+
+## Build/Test Commands
+- **Run PHPUnit Tests**: `vendor/bin/phpunit tests`
+- **Run Single Test**: `vendor/bin/phpunit tests/TestName.php`
+- **Composer Update**: `composer update`
+- **Composer Install**: `composer install`
+
+## Code Style Guidelines
+- **Class Naming**: Use `RL_MailWarmer_ClassName` format with underscores
+- **Method Naming**: Use snake_case for method names
+- **File Naming**: Use `class-rl-mailwarmer-name.php` for class files
+- **Database**: Use `rl_mailwarmer_` prefix for all tables
+- **Error Handling**: Use WP_Error for WordPress-specific errors, Exceptions for PHP-level errors
+- **Validation**: Always validate and sanitize inputs using WordPress functions
+- **Documentation**: Use PHPDoc blocks for classes and methods
+- **Security**: Follow WordPress security best practices (prepare SQL, validate nonces)
+- **Imports**: Place includes at the top, use require_once for class dependencies
+- **Type Hints**: Use PHP type hints for method parameters and return types
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