ObjectOSYour ontology in ObjectOS
What your ontology is on ObjectOS — the core the runtime runs, the projections authored beside it, where it lives, and what it is not.
The ontology is the software. On ObjectOS, your ontology is the definition of your business that the runtime executes: one typed, versioned body of ObjectStack metadata. The runtime derives the database schema, the REST API, the Console and the MCP tools from it, and enforces it on every call. This page maps the word onto this site; the full account is Business Ontology in the ObjectStack docs.
The core
Six kinds of thing make up the ontology itself:
| Core | What it declares | On this site |
|---|---|---|
| Objects and fields | The entities of the business and their typed attributes | Data Model, Field Types |
| Relations | Lookups and master-detail links between objects | Relationships |
| Actions | The operations a user — or, once its author exposes it, an agent — may invoke on a record | Actions |
| Permissions | Who may read, create, edit and delete what: permission sets, record access, field-level security | Permissions |
| Flows | The business processes: flows, record triggers, schedules, approvals, workflows | Automation |
| Agent and tool definitions | The AI agents the app ships with, their skills, and the tools they may call | Agents |
The projections
Views, dashboards, apps and translations are authored as metadata too, and they pass the same validation gate, but they are projections of the ontology, not part of it. Change the core and they follow; remove one and the business it showed is unchanged.
| Projection | What it projects | On this site |
|---|---|---|
| Views | An object's fields and permissions onto a list, form, kanban or calendar | Views, Forms |
| Dashboards | Queries over objects onto charts | Dashboards |
| Apps | Objects, views and actions, grouped into a navigable product | Apps |
| Translations | Every label, into a locale | Localization |
Where it lives on ObjectOS
One definition, in three forms:
| Form | What it is |
|---|---|
| Tenant metadata | What the AI Builder and Studio write: live metadata in your deployment. An AI Builder change queues for a person's approval before it applies |
| Repository source | What your developers and their coding agent write, with the AI skills: objectstack.config.ts and its metadata files, reviewed as pull requests |
| Compiled artifact | What os compile produces: objectstack.json, which a deployment boots — see Boot modes. Keep every published one (Backup) |
Whichever form you author in, the metadata passes the same validation gate before it runs. On either edition the ontology is yours: it is ordinary ObjectStack metadata, and you can export it and run it on the open-source ObjectStack runtime.
What it is not
- Not a knowledge ontology. There is no class inheritance, no axioms and no reasoner. The definition is validated, then run.
- Not a semantic layer over your existing systems. A semantic layer describes a business it does not run. Your ontology is the system: the database, API, UI and agent tools are derived from it. Connecting a database you already run is possible, read-only by default and early — see Extend Existing Systems.
Read further
This site documents the runtime; the ObjectStack site owns the concept:
- Business Ontology — what the word means, and how the runtime executes it
- How ObjectStack compares — beside knowledge ontologies, semantic layers, metadata platforms and AI code generation
- When to use ObjectStack — where it fits today, and where it does not
- The Ontology Is the Software — the long form