## ADDED Requirements

### Requirement: System overview exists at docs/devops/README.md
The system SHALL provide a `docs/devops/README.md` that serves as the entry point for DevOps engineers, including an index of all DevOps docs and a brief system overview.

### Requirement: Architecture doc exists at docs/devops/architecture.md
The system SHALL provide `docs/devops/architecture.md` documenting all components (Express server, PostgreSQL, Redis), their roles, ports, and data flow.

### Requirement: Environment variable reference exists at docs/devops/environment-variables.md
The system SHALL provide `docs/devops/environment-variables.md` documenting every environment variable with name, type, required/optional, default, and example value.