typebox

library1.1.36jsnpmunverified

TypeBox is a runtime type system that constructs JSON Schema objects from TypeScript-like type definitions, automatically inferring static TypeScript types via Type.Static. The current stable version is 1.1.36, with frequent releases following semantic versioning. It differentiates itself by providing a unified type system that works both at compile time (TypeScript type checking) and runtime (JSON Schema validation), making it ideal for API validation, data serialization, and building type-safe protocols. Unlike standalone validators like Ajv or Zod, TypeBox focuses exclusively on schema generation and type inference, leaving validation to JSON Schema validators.

serialization web-framework

npm install typebox

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INSTALL

IMPORT

SIG · TYPEBOX

typebox

serializationjavascriptv1.1.36

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

default (Type)

✓ import Type from 'typebox'

✗ const Type = require('typebox').default

The package exposes a default export. In CommonJS, require returns the default export directly, so you can use const Type = require('typebox'). Do not use destructuring { Type } as it won't work.

Type.String

✓ Type.String({ format: 'email' })

✗ Type.String({ format: 'email' })

Type.String is a function that returns a JSON Schema object. All type builders accept optional parameters for constraining the schema (e.g., format, minLength). Since typebox v1, all type definitions are function calls.

Type.Static

✓ type T = Type.Static<typeof schema>

✗ type T = Type.Static<schema>

Type.Static is a generic type that extracts the inferred TypeScript type from a schema. It must be used with typeof schema, not the schema value directly. This is a type-level operation, not a runtime function.

Shows how to define an object schema with TypeBox, infer the TypeScript type using Type.Static, and validate data with Ajv.

import Type from 'typebox'; const User = Type.Object({ id: Type.String(), name: Type.String(), email: Type.String({ format: 'email' }), age: Type.Optional(Type.Number({ minimum: 0 })) }); type UserType = Type.Static<typeof User>; // equivalent to: { id: string; name: string; email: string; age?: number } // Validate with any JSON Schema validator (not included) const Ajv = require('ajv'); const ajv = new Ajv(); const validate = ajv.compile(User); const result = validate({ id: '1', name: 'Alice', email: 'alice@example.com' }); console.log(result); // true

Debug

Known issues

gotchaType.Static is a type, not a function. It can only be used in type positions, not runtime.

fix

Use Type.Static<typeof schema> as a type annotation, not a runtime value.

affects: >=0.1

gotchaAll type builders (e.g., Type.String()) must be called as functions, even without arguments.

fix

Always use parentheses: Type.String(), not Type.String.

affects: >=1.0

gotchaType.Object requires properties to be registered with Type.* builders, not plain objects.

fix

Use Type.Object({ key: Type.String() }) instead of Type.Object({ key: { type: 'string' } }).

affects: >=1.0

Errors

Common errors & fixes

Cannot find name 'Type'. Did you mean the type 'Type'?

Using Type before importing or using Type as a type instead of value.

fix

Ensure you have the correct import: import Type from 'typebox'. If you see this in a type annotation, you might have a naming conflict.

TypeError: Type.String is not a function

Using Type.String (or other builders) as a property access without calling it as a function.

fix

Call Type.String() with parentheses, even if no arguments: Type.String().

Type 'typeof schema' does not satisfy the constraint 'TBoxSchema'.

Using Type.Static with a non-TypeBox schema object (e.g., a plain object literal).

fix

Ensure the argument to Type.Static is a schema built with TypeBox builders: Type.Static<typeof mySchema> where mySchema is constructed via Type.*.

Upgrade

Version history

1.1.36latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

15 hits · last 30 days

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Resources

githubhttps://github.com/sinclairzx81/typebox ↗

packagehttps://www.npmjs.com/package/typebox ↗

homepagehttps://sinclairzx81.github.io/typebox/ ↗