Directory

Open Source Packages

Libraries, frameworks, tools, and SDKs used by the apps in this directory — scored the same way as the apps themselves.

5929 packages

All Packages

91Health
Library npm

Zod

TypeScript-first schema validation with static type inference and zero dependencies.

43,990
MIT
Used by 277
91Health
Library npm

React Hook Form

Performant, flexible React forms built on hooks with minimal re-renders and built-in validation.

44,855
MIT
Used by 132
93Health
Library PyPI

Pydantic

Data validation and settings management using Python type hints, backed by a Rust core.

28,772
MIT
Used by 102
82Health
Library npm

@hookform/resolvers

Official React Hook Form adapters that plug 20+ schema-validation libraries — Zod, Yup, Joi, Valibot, ArkType and more — straight into useForm's resolver.

2,258
MIT
Used by 93
65Health
Library npm

Ajv

The fastest JSON Schema validator for Node.js and the browser, compiling schemas straight into executable validation code.

14,828
MIT
Used by 67
90Health
Library npm

Prisma Client

Auto-generated, type-safe database client for Node.js and TypeScript.

47,610
Apache 2.0
Used by 46
78Health
Library npm

validator.js

A dependency-free library of 100+ string validators and sanitizers for Node.js and the browser.

23,735
MIT
Used by 26
91Health
Library PyPI

jsonschema

The reference implementation of JSON Schema validation for Python, supporting every draft from 3 to 2020-12.

4,980
MIT
Used by 26
42Health
Library npm

ajv-formats

ajv-formats: JSON Schema Format Validators for Ajv v8+

228
MIT
Used by 25
48Health
Library npm

class-validator

Decorator-based property validation for TypeScript and JavaScript classes, on both Node.js and the browser.

11,837
MIT
Used by 23
82Health
Library Go

validator

Go struct and field validation using reflection-based tags, with cross-field, cross-struct, and nested slice/array/map diving support.

20,166
MIT
Used by 22
53Health
Library npm

Formik

Formik: Build React Forms Without the Tears - Docs & Guide

34,318
Apache 2.0
Used by 20
87Health
Library npm

Valibot

Modular, type-safe schema validation library with bundle sizes starting under 1KB

9,002
MIT
Used by 15
76Health
Library npm

joi

The most powerful schema description language and data validator for JavaScript

21,174
Other
Used by 14
52Health
Library PyPI

email-validator

Robust email address syntax and deliverability validation for Python

1,446
Other
Used by 14
60Health
Library npm

@apidevtools/swagger-parser

Parses, validates, and dereferences Swagger 2.0 and OpenAPI 3.x specs in Node.js and browsers

1,207
MIT
Used by 14
77Health
Library npm

zod-validation-error

Turns raw Zod validation issues into clear, human-readable error messages.

1,022
MIT
Used by 14
42Health
Library npm

GSAP

The industry-standard JavaScript animation library for tweening CSS, SVG, canvas, and UI with rock-solid cross-browser reliability.

28,405
Other
Used by 11
84Health
Library npm

express-validator

A chainable Express middleware that wraps validator.js to validate and sanitize incoming request data with minimal boilerplate.

6,232
MIT
Used by 8
89Health
Library PyPI

msgspec

A fast, zero-cost serialization and validation library for JSON, MessagePack, YAML, and TOML in Python.

4,105
BSD 3
Used by 8
47Health
Library PyPI

validators

A Python library for validating strings — emails, URLs, IPs, and more — without defining a schema.

1,124
MIT
Used by 8
55Health
SDK npm

msgraph-sdk-javascript

Official Microsoft Graph JavaScript SDK for calling the Graph API from Node.js and the browser.

833
MIT
Used by 8
90Health
Library Cargo

jsonschema

A high-performance JSON Schema validator for Rust with Python, Ruby, and WASM bindings

814
MIT
Used by 8
59Health
Library npm

utf-8-validate

Native addon that validates UTF-8 buffers at C++ speed, with a pure-JS fallback for unsupported platforms.

127
MIT
Used by 8

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