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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cel-go
The Go implementation of the Common Expression Language for fast, safe, embeddable expression evaluation.
Validator
Derive-macro struct validation for Rust, covering email, URL, length, range, and custom rules
MailChecker
Cross-language disposable email detector backed by a 55,000+ domain blocklist
schema-dts
TypeScript type definitions for Schema.org's JSON-LD vocabulary, giving structured data literals full autocomplete and compile-time validation.
@cfworker/json-schema
A dependency-free JSON Schema validator built to run inside Cloudflare Workers and other restricted JS runtimes without eval.
SQLModel
One model for SQLAlchemy and Pydantic, built by the creator of FastAPI to kill duplicate schema code.
instructor
Get reliable, validated structured JSON from any LLM provider using Pydantic models and automatic retries.
next-safe-action
Type safe and validated Server Actions for Next.js, with typed errors, middleware, and React hooks for execution state.
spatie/laravel-data
Powerful, type-safe data transfer objects and API resources for Laravel
fastjsonschema
Fast JSON schema validator for Python that compiles schemas to generated code
ajv-errors
Custom, human-readable error messages for Ajv JSON Schema validation
codemirror-json-schema
JSON Schema-powered linting, autocomplete, and hover tooltips for CodeMirror 6, across JSON, JSON5, and YAML documents.
jsonschema-specifications
Ships the official JSON Schema meta-schemas and vocabularies as a ready-to-use referencing Registry, so you never hand-copy spec files again.
EmailValidator
RFC-compliant email address validation for PHP with DNS, spoof, and strictness checks
marshmallow
An ORM/framework-agnostic Python library for converting complex objects to and from native datatypes, with built-in validation.
Flask-RESTful
A lightweight extension for Flask that adds Resource-based routing, request parsing, and output formatting for building REST APIs.
disposable-email-domains
A community-maintained blocklist of disposable email domains for filtering throwaway signups.
libphonenumber for PHP
A PHP port of Google's libphonenumber for parsing, formatting, validating, and storing international phone numbers.
Validator
Symfony's constraint-based validation component for checking PHP values, objects, and forms
OmegaConf
A hierarchical YAML-based configuration library that merges files, CLI args, and structured schemas with runtime type safety.
phonenumbers
A Go port of Google's libphonenumber for parsing, validating, and formatting international phone numbers.
envalid
Type-safe environment variable validation and cleanup for Node.js and Bun with zero runtime dependencies.
WTForms
A flexible, framework-agnostic form validation and rendering library for Python web development.
dataclasses-json
Encode and decode Python dataclasses to and from JSON with a single decorator or mixin.
