Comprehensive guide for developing on EspoCRM - metadata-driven CRM with service layer architecture
EspoCRM is a metadata-driven CRM platform where configuration lives in JSON files, business logic belongs in Services, and data access happens through ORM EntityManager. This skill enforces architectural patterns to prevent common mistakes like passing Container dependencies, bypassing the service layer, or implementing business logic in hooks.
Activate when developing custom EspoCRM modules, entities, relationships, hooks, services, API endpoints, or integrations. Use especially when: working with ORM (EntityManager required), implementing business logic (belongs in Services), creating hooks (use interfaces), modifying metadata (requires cache rebuild), or building custom field types.
BUSINESS LOGIC IN SERVICES, NOT HOOKS | DATA ACCESS VIA ENTITYMANAGER, NEVER DIRECT PDO | NEVER PASS CONTAINER AS DEPENDENCY
If you're accessing Container directly or writing business logic in hooks, you're violating architecture.
Setup Development Environment - Use ext-template, work in src/ directory (EspoCRM 7.4+), understand metadata structure: custom/Espo/Modules/{ModuleName}/Resources/metadata/
Access Data with EntityManager
use Espo\ORM\EntityManager;
public function __construct(private EntityManager $entityManager) {}
// Find entity
$account = $this->entityManager->getEntityById('Account', $id);
// Query with conditions
$collection = $this->entityManager
->getRDBRepository('Contact')
->where(['accountId' => $accountId])
->find();
Implement Business Logic in Services
namespace Espo\Modules\MyModule\Services;
use Espo\Services\Record;
class MyEntity extends Record {
public function customAction(string $id, object $data): object {
// Business logic here
$entity = $this->entityManager->getEntityById($this->entityType, $id);
// ... process ...
$this->entityManager->saveEntity($entity);
return $entity;
}
}
Register Hooks for Lifecycle Events
namespace Espo\Modules\MyModule\Hooks\Account;
use Espo\ORM\Entity;
use Espo\Core\Hook\Hook\BeforeSave;
class MyHook implements BeforeSave {
public function beforeSave(Entity $entity, array $options): void {
// Validation or side effects only
if ($entity->isAttributeChanged('status')) {
// React to changes
}
}
}
Rebuild Cache After Changes
bin/command rebuild
EspoCRM provides 7 hook types - ALWAYS use interfaces: BeforeSave (validation before save), AfterSave (side effects after save), BeforeRemove (validation before delete), AfterRemove (cleanup after delete), AfterRelate (relationship creation), AfterUnrelate (relationship removal), AfterMassRelate (bulk relationship operations).
For detailed information:
Correct Pattern:
✅ Service with injected dependencies
✅ EntityManager for data access
✅ Hooks using interfaces
✅ Type declarations on all methods
✅ Exceptions for error handling
Incorrect Patterns:
❌ Passing Container as dependency
❌ Direct PDO database access
❌ Business logic in hooks
❌ Hook base classes instead of interfaces
❌ Missing type declarations
bin/command rebuild)EspoCRM is metadata-driven with a service layer architecture.
Understand the metadata system. Use EntityManager for data. Implement business logic in Services. Use hooks for lifecycle events only. Rebuild cache after changes.
This is the EspoCRM way.