Shared Bundles - Policy Update

Status

The previous "shared Symfony bundles for domain logic" approach is deprecated for this migration.

Why:

• It couples island domains.
• It increases coordination cost across deployables.
• It conflicts with the anti-fragmentation policy in docs/migration/02-island-boundaries-and-performance.md.

Current Rule

Do not create shared bundles that contain mutable domain logic or ORM entities.

Explicitly forbidden in shared code:

• Article, Order, Vehicle, Customer entities
• Repository implementations
• Island business workflows
• Island migrations

Allowed Shared Code

Shared code must stay in one of the capped internal packages:

1. atraxion/contracts
2. atraxion/integration-sdk
3. atraxion/foundation

How To Handle Integrations

For payment, shipping, loyalty, vehicle providers, platform connectors, and supplier feeds:

1. Keep adapter implementation in the owning island.
2. Use atraxion/integration-sdk for common transport and reliability primitives.
3. Share DTO/event schemas via atraxion/contracts.

If a Bundle Seems Necessary

A new bundle-like shared module is allowed only if all are true:

1. Reused by at least 2 islands.
2. API is expected stable for 6+ months.
3. Contains no mutable domain entities/workflows.
4. Passed ADR review using docs/migration/03-architecture-review-checklist-template.md.

If any condition fails, keep it island-local.

Migration Guidance From Legacy Bundle Plan

1. Freeze new development on legacy shared bundle candidates.
2. Re-home domain entities and workflows to owning islands.
3. Keep only stable primitives/contracts in shared packages.
4. Track deviations via ADR with clear sunset date.