Data Validation & Schemas Packages
Runtime data validation and schema-definition libraries for catching malformed input before it reaches your application logic (Zod, Pydantic, Valibot).
Packages in Data Validation & Schemas
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kin-openapi
A Go library for parsing, validating, converting, and working with OpenAPI 2.0, 3.0, 3.1, and 3.2 documents.
email-validator
Robust email address syntax and deliverability validation for Python
@apidevtools/swagger-parser
Parses, validates, and dereferences Swagger 2.0 and OpenAPI 3.x specs in Node.js and browsers
zod-validation-error
Turns raw Zod validation issues into clear, human-readable error messages.
Schemars
Generate JSON Schema documents directly from Rust types
zod-openapi
Generate OpenAPI 3.x documentation directly from your existing Zod schemas.
@rjsf/core
The React engine that turns a JSON Schema into a fully working form
annotated-types
Reusable constraint metadata objects for use with Python's typing.Annotated
image-spec
Canonical Go types and embedded JSON Schema validation for the OCI Image Format specification.
jsonschema
Generate JSON Schema 2020-12 documents from Go types using reflection, struct tags, and doc comments.
jsonschema
A high-performance JSON Schema validator for Rust with Python, Ruby, and WASM bindings
TypeBox
JSON Schema type builder with static TypeScript type inference and zero dependencies.
express-validator
A chainable Express middleware that wraps validator.js to validate and sanitize incoming request data with minimal boilerplate.
json_repair
Repair malformed JSON from LLMs, APIs, logs, and user input — a drop-in fallback for json.loads().
msgspec
A fast, zero-cost serialization and validation library for JSON, MessagePack, YAML, and TOML in Python.
gojsonschema
A Go implementation of JSON Schema, supporting draft-04, draft-06, and draft-07 validation.
validators
A Python library for validating strings — emails, URLs, IPs, and more — without defining a schema.
govalidator
A comprehensive Go package of string, numeric, and struct validators and sanitizers, modeled on validator.js.
graphql-scalars
A drop-in library of 70+ precise, spec-compliant GraphQL scalar types for emails, dates, IDs, currencies, and geodata.
typing-inspection
Runtime introspection tools for Python type annotations, maintained by the Pydantic team
json-logic-js
A lightweight JavaScript engine for building, storing, and executing JsonLogic rules across the front-end, back-end, and database.
jsonschema
A compliant, dependency-light Go library for compiling and validating JSON Schema across five draft versions, with rich hierarchical errors.
openapi3-ts
Typed TypeScript models and a fluent builder DSL for authoring OpenAPI 3.0, 3.1, and 3.2 contracts.
referencing
Implementation-agnostic JSON reference resolution for JSON Schema, OpenAPI, and beyond
