Composition

Compose provides static methods for deriving new schemas from existing ones. All methods return new schema objects - input schemas are never mutated. The TypeScript types are inferred at compile time; the output is valid JSON Schema at runtime.

Methods

Method	Description
extend	Add properties to a base schema
pick / omit	Keep or remove specific properties
partial / required	Make all properties optional or required
intersection	Combine schemas with allOf
equivalent	Declare two schemas as semantically equivalent (equivalentClass / equivalentProperty)
discriminatedUnion / narrow	oneOf with type discriminator
getDefaults	Extract declared default values

All examples use the bookstore domain. Composed schemas build on each other - see Getting Started for the basics.

Related

• register - register composed schemas before use
• instantiate - coerce values through composed schemas
• materialize - fill defaults through composed schemas

See also

• Bookstore domain - base schemas used throughout composition examples
• Argument conventions - how composed schemas work as SchemaRef
• Graph-native authoring - when to extract vs compose