npm

@hyperjump/json-schema

A JSON Schema validator with support for custom keywords, vocabularies, and dialects

hyperjump-io/json-schemaNew releases in your daily digest, changelog included.

Latest stable

1.18.1

Last release today
14 Nov 2026
Ships fairly regularly
a new release about every 6 weeks
Rarely documented
notes for 10 of the last 60 stable releases
Nothing withdrawn
no release was ever pulled
7 years old
124 releases · first in 2020

Releases on this page

Older releases

Drag across the ruler to compare, or tap a release to open it.

1.18.114 Nov 2026
A schema can no longer give itself or an embedded schema a file: $id unless it was loaded from the filesystem. Before this fix, a schema retrieved fro
Security

A schema can no longer give itself or an embedded schema a file: $id unless it was loaded from the filesystem. Before this fix, a schema retrieved from the web could use a file: $id to make its $refs resolve against a file: base and load local schema files. A file: id is now allowed only when the URI it resolves against is also a file: URI.

Fixes

multipleOf gives correct results for very small divisors and very large values. Values much smaller than the divisor, like 1e-20 with multipleOf: 1, no longer pass. (#140, by @MohitSAGAR11)

A schema that fails meta-validation is rejected every time it's validated. Before, only the first validation failed, and later validations used the invalid schema as if it had passed. (#134, by @MohitSAGAR11)

Fixed the type of SchemaParameter.schema in the openapi-3-1 types: it was OasSchema32 and is now OasSchema31. (#137, by @tarunagnihotri534)

JSON Schema v1 dialect

The format keyword respects shouldValidateFormat. It still validates formats by default, but now you can turn that off.

The date-time format validates against RFC 9557, which allows time zone and suffix tags such as 2026-11-14T12:00:00-08:00[America/Los_Angeles]. The v1 handler uses the https://json-schema.org/format/date-time URI. The RFC 3339 handler that draft-04 through draft-2020-12 use moved to https://json-schema.org/format/draft-04/date-time.

$dynamicRef no longer accepts a leading #. Write "$dynamicRef": "foo", not "$dynamicRef": "#foo".

Performance

Schema registry lookups take constant time whether or not you pass a browser. Browsers look up registered schemas in the registry instead of copying the registry into their own cache. As a result, browsers always see the current registry, and a schema you unregister is no longer found by browsers that already exist. (#131, by @Kaileshwar16)

An instance node now computes its URI only once. This speeds up output formats and plugins that record instance locations. Validating a 150KB GitHub workflow with BASIC output went from about 3.8ms to 3.0ms.

Internal

The test runners support the unified JSON Schema test suite and filter format tests by their format-assertion and format-annotation tags.

Adopted @stylistic/eslint-plugin 6.0.0.

Full Changelog: v1.18.0...v1.18.1

Your coding agent can read these notes before it upgrades. Set up the MCP server →

Release timeline

124 releases since 2020

1.18.05 Oct 2026

You can now add your own output formats with setOutputFormat from @hyperjump/json-schema/experimental . An output format handler is called for each ev

Custom output formats

You can now add your own output formats with setOutputFormat from @hyperjump/json-schema/experimental. An output format handler is called for each evaluation with the validation options. It can return an EvaluationPlugin that collects results during evaluation, and a getErrors function that builds the errors of the output when validation fails. FLAG, BASIC, and DETAILED are now registered this way too.

This lets other packages add output formats without this package depending on them. For example, @hyperjump/json-schema-errors uses it to add a JSE output format with human readable error messages.

import { setOutputFormat } from "@hyperjump/json-schema/experimental";

setOutputFormat("FAILED_KEYWORDS", (options) => {
  const plugin = new FailedKeywordsPlugin();
  return { plugin, getErrors: () => plugin.keywords };
});

const output = await validate("https://example.com/schema1", 42, "FAILED_KEYWORDS");

In TypeScript, OutputFormats and ValidationOptions are now interfaces, so a package that adds an output format can augment them with its output type and options. validate, Validator, and interpret infer the output type from the output format you pass. See the README's Output Formats section for the full example. The README now documents the DETAILED output format as well.

Fixes

const and enum no longer follow references in their values. In draft-04, draft-06, and draft-07, a value like { "const": { "$ref": "#/definitions/foo" } } now compares against the literal object instead of the referenced schema. (#129)

Full Changelog: v1.17.9...v1.18.0

Open source →

Additional notes

This project publishes no release notes. Between v1.17.9 and v1.18.0 there were 4 commits, 3 of them substantive:

Test CI on lts/* and latest Node instead of 20 and 22
const and enum should not follow references (#129)
Add an output format registry

1.17.93 Oct 2026

Build schema documents without cloning the schema

Build schema documents without cloning the schema
Use @hyperjump/json-pointer for instance pointers
Remove iteration helper overhead from array and anyOf keywords
Fix stack overflow with many errors and speed up annotations
Reduce unevaluated keyword and interpreter overhead
Reduce per-evaluation overhead
Ignore a local benchmark directory
Fix slowdown when validating many small instances
Speed up compilation and plugin-based evaluation
Reduce AST memory and speed up interpretation
Improve JSON AST construction performance
Add Instance.fromJson with source location data
Update dependencies
Fix a bunch of random typos and a minor bug

Full Changelog: v1.17.8...v1.17.9

Open source →

Additional notes

This project publishes no release notes. Between v1.17.8 and v1.17.9 there were 15 commits, 13 of them substantive:

Fix a bunch of random typos and a minor bug
Add Instance.fromJson with source location data
Improve JSON AST construction performance
Reduce AST memory and speed up interpretation
Speed up compilation and plugin-based evaluation
Fix slowdown when validating many small instances
Ignore a local benchmark directory
Reduce per-evaluation overhead
Reduce unevaluated keyword and interpreter overhead
Fix stack overflow with many errors and speed up annotations
Remove iteration helper overhead from array and anyOf keywords
Use @hyperjump/json-pointer for instance pointers
Build schema documents without cloning the schema

1.17.85 Aug 2026

Allow instance objects to have null constructors

Allow instance objects to have null constructors

Full Changelog: v1.17.7...v1.17.8

Open source →

Additional notes

This project publishes no release notes. Between v1.17.7 and v1.17.8 there were 2 commits, 1 of them substantive:

Allow instance objects to have null constructors

1.17.76 Jul 2026

Fix type for Keyword.annotation

Fix type for Keyword.annotation
Pin undici to v7
fix: correct non-transitive keywordComparator in validation.js (#123)
fix: avoid trailing comma in jsonStringify when replacer skips last property (#120)
Make validator serialization a first-class feature (#118)
Serialize and restore compiled schema (#115)
add optional id to plugins (#113)

Full Changelog: v1.17.6...v1.17.7

Open source →

Additional notes

This project publishes no release notes. Between v1.17.6 and v1.17.7 there were 8 commits, 7 of them substantive:

add optional id to plugins (#113)
Serialize and restore compiled schema (#115)
Make validator serialization a first-class feature (#118)
fix: avoid trailing comma in jsonStringify when replacer skips last property (#120)
fix: correct non-transitive keywordComparator in validation.js (#123)
Pin undici to v7
Fix type for Keyword.annotation

1.17.624 Apr 2026

Pin undici version to work around a bug

Update uuid
Pin undici version to work around a bug
Type fixes
Actually run v1 extension tests

Full Changelog: v1.17.5...v1.17.6

Open source →

Additional notes

This project publishes no release notes. Between v1.17.5 and v1.17.6 there were 5 commits, 4 of them substantive:

Actually run v1 extension tests
Type fixes
Pin undici version to work around a bug
Update uuid

1.17.516 Mar 2026

fix(format): use RFC1123 hostname validator for legacy drafts

Cleanup annotation tests
fix(format): use RFC1123 hostname validator for legacy drafts (#109)
When bundling remove empty $defs if nothing was bundled
fix: use correct subscription key in publishAsync (#106)
Fix incorrect import in README for enabling format validation
Fix requireAllExcept runtime error (#100)

Full Changelog: v1.17.4...v1.17.5

Open source →

Additional notes

This project publishes no release notes. Between v1.17.4 and v1.17.5 there were 7 commits, 6 of them substantive:

Fix requireAllExcept runtime error (#100)
Fix incorrect import in README for enabling format validation
fix: use correct subscription key in publishAsync (#106)
When bundling remove empty $defs if nothing was bundled
fix(format): use RFC1123 hostname validator for legacy drafts (#109)
Cleanup annotation tests

1.17.419 Jan 2026

Don't short circuit in dependencies keyword

Don't short circuit in dependencies keyword
Cleanup
fix: typos are refactored (#97)
docs: fix incorrect test watch mode instruction (#96)
feat(openapi): export all oas types (#94)
fix(test-utils): use parentPath for recursive Dirent (#93)

Full Changelog: v1.17.3...v1.17.4

Open source →

Additional notes

This project publishes no release notes. Between v1.17.3 and v1.17.4 there were 7 commits, 6 of them substantive:

fix(test-utils): use parentPath for recursive Dirent (#93)
feat(openapi): export all oas types (#94)
docs: fix incorrect test watch mode instruction (#96)
fix: typos are refactored (#97)
Cleanup
Don't short circuit in dependencies keyword

1.17.34 Jan 2026

Remove Reference type from Callbacks definition

Fix types
Remove Reference type from Callbacks definition (#92)
Fix: allowEmptyValue is valid only for query parameters.
Change 'mappings' to 'mapping' in Discriminator type
fix typo: Rename 'additionOperations' to 'additionalOperations'
fix: Remove 'VERBOSE' from OutputFormat type in outdated type definition

Full Changelog: v1.17.2...v1.17.3

Open source →

Additional notes

This project publishes no release notes. Between v1.17.2 and v1.17.3 there were 8 commits, 6 of them substantive:

fix: Remove 'VERBOSE' from OutputFormat type in outdated type definition
fix typo: Rename 'additionOperations' to 'additionalOperations'
Change 'mappings' to 'mapping' in Discriminator type
Fix: allowEmptyValue is valid only for query parameters.
Remove Reference type from Callbacks definition (#92)
Fix types

1.17.214 Nov 2025

Type fix Full Changelog : v1.17.1...v1.17.2

Type fix

Full Changelog: v1.17.1...v1.17.2

Open source →

Additional notes

This project publishes no release notes. Between v1.17.1 and v1.17.2 there were 2 commits, 1 of them substantive:

Type fix

1.17.110 Nov 2025

This project publishes no release notes. Between v1.17.0 and v1.17.1 there were 3 commits, 2 of them substantive:

This project publishes no release notes. Between v1.17.0 and v1.17.1 there were 3 commits, 2 of them substantive:

Fix type errors
Make 2020-12 format a distinct keyword

1.17.07 Nov 2025

This project publishes no release notes. Between v1.16.5 and v1.17.0 there were 16 commits, 15 of them substantive:

This project publishes no release notes. Between v1.16.5 and v1.17.0 there were 16 commits, 15 of them substantive:

Use v1 tests
Add framework for supporting format validation
Add date and time formats
Add URI/IRI formats
Add support for IP formats
Add uuid format handler
Add support for uri-template format
Add support for regex format
Add support for the json-pointer format
Add support for the relative-json-pointer format
Add support for the hostname format
Add support for email formats
Skip hostname A-label tests that aren't covered
Refactor and cleanup for formats
Update formats to use @hyperjump/json-schema-formats

1.16.526 Oct 2025