Conventions

ID Formats

Main Network

Standard 26-character ULIDs:

01JXXXXXXXXXXXXXXXXXXXXXXXXX

ULIDs are sortable by creation time and globally unique.

Test Network

Test IDs use an II prefix + 24 characters:

IIXXXXXXXXXXXXXXXXXXXXXX

The II prefix is impossible in real ULIDs (which start with time-based encoding), making test data unambiguously identifiable. Test data routes to separate storage buckets and databases.

IPLD-Style Links

Version links use the IPLD convention for content-addressed references:

{ "/": "bafyreig..." }

This provides compatibility with content-addressed ecosystems. The CID (Content Identifier) is computed locally using the same algorithm, providing content-addressing guarantees without requiring IPFS infrastructure.

CID Format

CIDs are computed from the manifest JSON using:

• SHA-256 hash of the canonical JSON representation
• Base32 encoding with the bafyrei prefix (CIDv1, dag-cbor, SHA-256)

Network Header

Set X-Arke-Network to select the network:

Schema Versioning

Entity schemas follow the namespace/type@version convention:

arke/eidos@v2      -- Base entity schema
arke/file@v1       -- File profile
arke/collection@v1 -- Collection profile

When schemas evolve, the version number increments. The system can validate entities against the schema version specified in their schema field.