Domain glossary¶

Atlas is an extensible software catalog that an operator assembles for a particular deployment. The terms below have specific meanings in Atlas documentation.

Catalog model¶

Catalog Entity: A globally identified catalog record whose common identity and metadata are independent of its kind-specific details.
Entity Kind: A registered category of Catalog Entity that defines its kind-specific meaning and details while retaining the entity's identity. Standard Catalog registers system, component, resource, group, and actor; the APIs plugin registers api.
Entity Kind Handler: The plugin-supplied implementation of an Entity Kind's create, update, and delete behavior. It persists and serializes kind-specific fields, and vetoes a delete that would leave the catalog inconsistent.
Entity Service: The single transactional path for authorizing, validating, resolving the Entity Kind Handler, persisting, and auditing every change to a Catalog Entity. No other code path may create, update, or delete one.
Entity Intent: A proposed state for a Catalog Entity submitted by an ingestion pipeline for validation and reconciliation through the Entity Service.
Unavailable Entity: A read-only Catalog Entity whose Entity Kind Handler is not registered, for example because its owning plugin was removed from the distribution. Its identity and relationships are preserved.
Facet: An optional structured aspect of a Catalog Entity, owned by a plugin, with a lifecycle separate from the owning Entity Kind's details. The Database Schema plugin's ER data is a Facet on resource entities rather than a field of the resource kind.
Relation: A derived, typed edge between two Catalog Entities, such as ownedBy, partOf, dependsOn, providesAPI, consumesAPI, or hasMember. Relations are recomputed from entity fields and cannot be written directly. They differ from Architecture Relationships.
Architecture Relationship: A directed, user-authored interaction between two Catalog Entities. It has a label, optional technology and interaction kind, and a manual or YAML origin. It is populated by a manifest's relationships: block or created manually; it is not derived or regenerated from entity specifications.
Removed: A Catalog Entity's soft-decommissioned status. Its row, kind details, and existing relations remain intact, and its name remains reserved. Removed entities are hidden from default list and search views. See Removed, Revive, and Purge.
Revive: The action that returns a Removed entity to active, preserving its id, relations, and audit history. It does not create a new entity or restore one by name.
Purge: The explicit, permission-gated destructive action available only from Removed. It permanently deletes a Catalog Entity's row and frees its name for a new entity with a new id. Blocked by any still-active reference to it.
Purge Grant: A permission that an owner Group's admins assign to a specific member, or that a member holds through global-admin status. It authorizes that member to Purge entities owned by the Group, including source_kind=yaml ones.

Ingestion and arbitration¶

Entity Claim: The association between a Catalog Entity's ref and the Source Kind (manual or yaml) that controls its fields. For yaml, it also identifies the registered repository.
Claim Arbitration: The check an ingestion run performs, before submitting an Entity Intent, deciding whether a ref's existing claim yields to, rejects, or is overwritten by an incoming YAML claim.
Conflict Record: A persisted record of a rejected ingestion claim, including its repository, ref, and reason. It remains visible on the blocked entity and in the admin even if the blocking repository is later deleted.
Adoption: The one-way conversion, by a permitted user, of a manual entity's claim to source_kind=yaml for a named repository. A YAML claim cannot be adopted back to manual.

Plugin composition¶

Plugin: A trusted, operator-selected extension in an Atlas deployment that contributes capabilities through supported extension points. Plugins are deployment code. They are neither sandboxed nor installable from the running application.
Plugin Release: One versioned delivery unit whose optional backend and frontend artifacts are installed and verified together.
Extension Point: A named, typed point where core or a plugin declares that other plugins may contribute an implementation, such as a route, tab, widget, or Entity Kind, without directly mutating a shared registry. Every extension point declares one of three cardinalities: a collection (many contributions, like detail tabs), a singleton (exactly one selected implementation), or keyed (many contributions distinguished by a unique key, like Entity Kinds).
Contribution: The immutable declaration a plugin exports into an Extension Point, such as a route, detail tab, or home widget. Plugins export contributions as data at module-import time and never mutate a registry as an import side effect.
Capability: A named, versioned service contract that one plugin publishes and another resolves by id rather than by importing the provider's models or internals. A missing required capability makes composition fail. A missing optional capability makes its dependent contributions inapplicable.
Distribution: A versioned, reproducible selection of core, the Plugin API, and specific Plugin Releases that an operator builds and deploys as one Atlas installation.
Deployment Manifest: The operator-authored, source-controlled file that names the Plugin Releases and registry sources that compose a Distribution.
Distribution Lock: The composer-generated record of exact resolved artifact versions for a Distribution's manifest; integrity comes from uv.lock and package-lock.json. It is used only to build reproducible images; containers do not download anything when they start.
Composer: The build-time tool that resolves a Deployment Manifest into a Distribution Lock and generates the backend and frontend composition for the selected Plugin Releases.

People and access¶

Operator: The party that assembles, configures, and deploys an Atlas installation, including the selected plugins.
Actor: A Catalog Entity representing a person. It can be referenced by catalog relationships whether or not that person can log in to Atlas.
Principal: The login identity for a person or system. An Actor can optionally link to one Principal, but they are distinct records with distinct lifecycles.
Policy Evaluator: The distribution-selected singleton implementation that decides whether a Principal holds a permission on a resource. The default is built-in role-based access control; an external policy engine is another option.