The only point where everything connects.

This stratum is the composition root: the only place that knows all strata and connects them. Here live main(), dependency injection configuration, and environment initialization.

The Wiring is the point of total materialization — where the abstract definitions from 00_nucleo meet their concrete implementations from 03_infra.

The Wiring has near-zero logic. It orchestrates — it does not create. Any if/else related to business rules found here is a structural defect and belongs to 01_core.

• Application entry point (main(), index.ts, app.py)
• Dependency injection configuration
• Environment variable loading
• Server initialization

This is the only stratum that can import from all numbered layers.

• ✅ 04_wiring → 00_nucleo
• ✅ 04_wiring → 01_core
• ✅ 04_wiring → 02_shell
• ✅ 04_wiring → 03_infra
• ❌ 04_wiring → _lab

/**
 * Crystalline Lineage
 * @spec 00_nucleo/specs/application-bootstrap.md
 * @layer L4
 */
import { IUserRepository } from '../01_core/domain/user';
import { UserController } from '../02_shell/api/user-controller';
import { PostgresUserRepository } from '../03_infra/database/postgres-user-repository';

// Dependency injection — the only place where implementations are assigned to interfaces
const repository: IUserRepository = new PostgresUserRepository(config.database);
const controller = new UserController(repository);

export function main() {
  const app = createServer();
  app.use('/users', controller.routes);
  app.listen(3000);
}

main();

• Do not generate business logic in this stratum
• Verify that implementations from 03_infra satisfy the interfaces required by 02_shell and defined in 01_core
• Ensure that mandatory environment variables are validated on bootstrap