Deprecation Policy

This policy reflects what is actually implemented in code as of the current monorepo state.

Current Implementation Check

Component	File	Deprecation Header Logic
Edge gateway responses	apps/edge-gateway/src/routes/proxy.ts	No Deprecation/Sunset header emission logic present
Platform API	apps/platform-api/src/server.ts	No middleware inserting deprecation headers

Because no automatic headers exist, deprecation notices must be communicated via documentation and release notes.

Manual Process

1. Track API removals in apps/docs/content/changes/changelog.md.
2. Communicate timelines via _meta/docs-scope and section-specific guides.
3. Provide migration details alongside breaking-change commits.

Timelines

• Minimum notice: 6 months before removal (documented, not enforced by code).
• Migration guidance: Added to the relevant doc when deprecation PR merges.

Cryptography-Specific Deprecations

Actual algorithm availability is enforced by the PQC provider registry (packages/cryptography/src/provider.ts). Algorithm sunsets (e.g., Dilithium → Falcon) are recorded in changes/crypto-sunset.md; no automated enforcement exists.

Future Work

• Implement shared middleware that injects Deprecation and Sunset headers when an endpoint is flagged.
• Surface sunset metadata via packages/shared-kernel constants so all services can consume the same schedule.