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Domain Ontologies

Domain Ontologies

The Domain Ontologies serve as the definitive registry of standardized data structures and resource definitions for the Open Microservice Initiative (OMI). While the Service Mechanics define the “verbs” (how services communicate), the Domain Ontologies define the “nouns”, the specific data objects that allow disparate services to function as a single, cohesive ecosystem.

Defining the Universal Language

A primary barrier to modular software assembly is “Semantic Drift”, the tendency for every developer to design unique schemas for identical business objects . This results in “Mystery JSON”: data structures that look similar but remain architecturally incompatible, requiring bespoke integration logic for every new project .

The OMI eliminates this “CRUD ritual” by providing Master Schemas for common business domains . By adhering to these ontologies, developers ensure that their services are:

  • Instantly Swappable: A “Post Management” service from Vendor A can be replaced by Vendor B without changing the consumer’s code, or just by swapping an API endpoint URL.
  • AI-Native: Standardized schemas allow AI agents to programmatically understand and manipulate data without human intervention.
  • Generic by Design: OMI ontologies are engineered to be unopinionated. A single “Content” ontology can handle everything from microblogging and image-centric posts to long-form articles and video metadata.

How to Use These Ontologies

Each subpage in this section provides a Master Schema and the corresponding technical mandates for that specific domain. Each ontology is hosted as a part of our git repository, allowing you to clone, fork, and contribute improvements. To implement an OMI-compliant service using these ontologies, follow these steps:

  1. Select Your Domain: Choose the ontology that matches your service’s “Atomic Responsibility” (e.g., Content Management or E-Commerce).
  2. Download the Master Schema: Use the provided OpenAPI definition as the “Gold Standard” for your implementation.
  3. Implement Logic, Not Design: Focus your engineering effort on the quality of the service logic rather than designing new API endpoints.
  4. Validate Compliance: Use the Compliance CLI to verify that your service’s interface matches the Master Schema perfectly.

The Ontology Registry

The Initiative currently maintains the following ratified domain ontologies: