Add-ons

Add-ons are versioned, configurable platform capabilities generated around the product domain. Current prefab module generation is centered on the Python/FastAPI target; target preflight and the product UI are authoritative for availability elsewhere.

Authentication

The auth module can provide:

• local email/password signup and login;
• password policy;
• JWT configuration with secret resolved from an environment variable;
• authenticated-user endpoint and logout behavior;
• optional OAuth providers such as Google, GitHub, Auth0, Firebase, Microsoft, Apple, and generic OIDC;
• actor assignment/context used to resolve modeled personas and session attributes.

OAuth client IDs and secrets are runtime values. The model stores their environment-variable names.

Notifications

The notifications module declares:

• delivery channels and providers;
• templates;
• event triggers;
• recipient resolution from event fields, authenticated users, or explicit addresses;
• enabled state and version.

Domain events remain the integration point. Product behavior emits meaning; the notification module delivers it.

File upload

The file-upload module supports:

• local filesystem or Amazon S3 storage;
• default MIME-type and size policy;
• per-field policy overrides;
• generated storage abstraction and routes;
• upload logging;
• authentication guard when the app has auth enabled.

Local storage is suitable for development or a single durable node. Multi-instance deployment needs shared object storage.

Audit trail

The audit module subscribes to domain events for selected aggregates and persists audit entries. Configuration can select tracked aggregates and retention intent.

Audit trail is not a backup and does not replace business event modeling. It is an operational record of observed changes.

Add-on configuration rule

An explicitly authored disabled module remains disabled; inference must not silently enable it. When no module configuration exists, modelARch may recommend or infer a module from product needs, but the decision remains inspectable.

Support matrix

Module	Product policy in model	Runtime secrets	Domain connection
Auth	password/JWT/provider policy	signing key, OAuth credentials	actor identity and assignments
Notifications	channels/templates/triggers	SMTP/provider credentials	domain events
File upload	storage and per-field policy	storage credentials	file-typed fields
Audit trail	tracked aggregates/retention	database/runtime config	domain events

See Technology stack and add-ons and Configuration and secrets.