Open-source alternatives to Validator.js

This project is a jQuery-based form validation library designed to verify HTML form input values on the client side before submission. It functions as an input validator that enforces data integrity constraints through rule-based verification and value normalization. The library focuses on web accessibility compliance by linking error messages to input fields via ARIA attributes, ensuring that screen readers can announce validation failures to the user. The system supports the creation of custom validation rules and the transformation of raw input strings through a normalization pipeline. Co

This library is a PHP framework for enforcing data integrity and business rules by validating scalar values and complex object structures against predefined constraints. It provides a structured approach to inspecting object graphs and property metadata, ensuring that data conforms to expected requirements before it is processed by an application. The framework distinguishes itself through a metadata-driven mapping system that uses reflection or configuration files to apply rules directly to object properties. It supports contextual rule orchestration, allowing developers to organize constrai

Eureka is a framework for building structured data-entry interfaces and forms in Swift for iOS applications. It provides a declarative UI layout engine and a dynamic input interface to define fields, sections, and row layouts through a configuration layer. The system distinguishes itself through dynamic interface management, including conditional visibility and interaction control that reacts to real-time user changes. It supports complex input behaviors such as expandable row rendering, multivalued field management for inserting or deleting similar rows, and custom keyboard navigation that s

Arktype is a TypeScript runtime validation library and schema orchestrator. It synchronizes TypeScript types with runtime data validation, allowing users to define type-safe schemas that ensure unknown data adheres to specific structures during application execution. The project distinguishes itself by using set-theory type analysis to determine intersections and subtype compatibility, alongside JIT-compiled validation functions for optimized performance. It supports advanced type modeling through branded type constraints, recursive alias resolution, and the ability to generate runtime valida

Revel is a full-stack web framework and toolkit for building applications with the Go language. It implements a model-view-controller architecture to separate business logic from user interface rendering, providing a comprehensive system for routing, parameter binding, and session management. The project distinguishes itself with a high-productivity development environment featuring automatic code compilation and hot-reloading, which refreshes the application state and templates upon file changes without requiring manual restarts. It also employs reflection-based parameter binding to automati

Pydantic is a data validation and serialization library that enforces schema constraints and performs type conversion on complex data structures. It utilizes standard Python type annotations to define data models, allowing developers to establish structured schemas that automatically enforce business rules and constraints without the need for custom domain-specific languages. The library distinguishes itself by transforming high-level model definitions into optimized code during initialization to minimize runtime overhead. It supports recursive validation for nested data structures and employ

This library is a PHP framework designed for validating and sanitizing incoming data. It provides a structured approach to ensuring that information conforms to expected formats and integrity requirements before it is processed or stored by an application. The project utilizes a fluent interface to construct validation logic, allowing for the definition of complex rules through chainable methods. It employs a strategy-based execution model where individual validation components are encapsulated and can be dynamically assigned to data fields. When validation fails, the system uses an exception

Handsontable is a JavaScript data grid that provides a spreadsheet-like interface for managing and editing large datasets within web applications. It functions as a virtualized data table that renders only visible cells to maintain performance, paired with a synchronization layer that binds the grid to underlying data structures. The project distinguishes itself through a built-in spreadsheet calculation engine for evaluating mathematical and logical expressions and a dedicated tool for exporting grid content into Excel XLSX files. It ensures interoperability with external spreadsheet softwar

This project is a Python framework for building command-line interfaces by converting standard functions into executable programs. It uses type hints to automatically infer and generate argument parsers, validation logic, and help documentation, allowing developers to define complex terminal applications through simple function signatures. The framework distinguishes itself through a decorator-driven registration system that enables the construction of hierarchical command trees. It supports dependency injection to manage shared state and runtime configuration across subcommands, and it utili

async-validator is a JavaScript schema validation library and asynchronous data validation engine. It verifies complex object structures and nested arrays by applying recursive rules and non-blocking, promise-based execution to ensure data integrity. The library functions as both an object constraint validator and a data transformation pipeline. It allows for the sanitization, coercion, and formatting of input values through a sequence of functions that run before and after the primary validation process. The engine covers a range of capabilities including recursive nested validation, the en

This project is an ESLint plugin and static analysis tool designed to enforce best practices, prevent bugs, and maintain code quality in React projects. It functions as a specialized JSX linter that analyzes the syntax and structure of components to detect anti-patterns and API misuse. The plugin distinguishes itself by providing deep analysis of React-specific patterns, such as detecting state race conditions, preventing nested component definitions, and identifying unstable references that cause unnecessary re-renders. It also includes security hardening rules to identify vulnerabilities li

Joi is a JavaScript data validation library used to define schemas that validate, cast, and sanitize data objects. It functions as an object schema validator and parser, ensuring that input data matches specific types and formats before it is processed by an application. The library features a conditional validation engine capable of dynamic schema enforcement, where validation logic and dependencies change based on the values of other keys within an object. It also serves as a data casting and sanitization tool, transforming input values into target types and removing sensitive keys from the

Superstruct is a JavaScript and TypeScript data validation library used to verify that data structures match defined shapes and types. It functions as a composable schema builder and a TypeScript schema validator, ensuring that runtime data checks remain synchronized with static type definitions. The library features a data coercion engine that transforms input values or injects default values before the validation process is executed. It enables the creation of complex validation rules by nesting, merging, or omitting properties from existing structures. Its capabilities cover the validatio

Vector is a high-performance observability data pipeline designed to collect, transform, and route logs, metrics, and traces across distributed infrastructure. It functions as a modular engine that decouples data ingestion from processing and transmission, utilizing a component-based architecture to connect diverse sources to multiple destinations. The project distinguishes itself through a focus on reliability and flow control. It implements backpressure-aware data movement to prevent data loss during traffic spikes and utilizes disk-backed event buffering to ensure durability during network

Prefect is a workflow orchestration platform designed to define, schedule, and monitor complex data pipelines as Python code. It functions as a container-native engine that wraps individual tasks in isolated environments, ensuring consistent dependencies and resource allocation across diverse infrastructure. By utilizing a state-machine-based orchestration model, the system tracks execution progress through discrete transitions and persistent event logs to maintain reliable and observable task processing. The platform distinguishes itself through a decoupled worker-API architecture, which sep

This PHP library provides tools for generating and validating universally unique identifiers according to RFC 4122 standards. It implements a generation tool for creating version 1, 3, 4, and 5 identifiers, as well as sequential and Nil UUIDs. The library features specialized capabilities for transforming identifiers between hexadecimal strings, binary bytes, integers, and date objects. It supports the generation of sequential identifiers to improve database indexing and storage performance, as well as deterministic name-based identifiers using MD5 or SHA-1 hashing. The project includes a va

Go Package of validators and sanitizers for strings, numerics, slices and structs

is.js is a JavaScript validation library and data type checker. It provides a suite of utilities to verify whether variables are primitives, arrays, functions, or specific object types. The project allows for the implementation of custom validation logic and the use of naming namespaces to override default rules and regular expressions. It covers a broad range of validation capabilities, including numeric arithmetic properties, date and time analysis for relative and absolute ranges, and string format verification for patterns such as emails, URLs, and IP addresses. The library also includes

js-xss is an HTML XSS sanitizer and whitelist-based HTML filter designed to remove malicious code from untrusted HTML. It serves as a tool for cross-site scripting prevention and user-generated content management by cleaning HTML strings to ensure safe browser rendering. The library includes a CSS style validator to scrub inline styles against a whitelist and an HTML content purifier capable of stripping all tags to extract raw text. It allows for custom HTML filtering through the definition of specific rules and handler functions to control permitted elements and attributes. The tool covers

This is an HTML sanitization library designed to remove dangerous tags and attributes from user-submitted HTML to prevent cross-site scripting attacks. It functions as a content filter that whitelists specific elements and attributes while escaping or discarding unauthorized markup. The project includes an HTML transformation engine that allows for the modification or replacement of tags and attributes using custom logic. It also features a CSS style validator to clean inline properties against permitted patterns and a system for resource URL validation to restrict hostnames and schemes. The

DOMPurify is a security-focused library designed to sanitize untrusted HTML input, preventing cross-site scripting attacks by stripping malicious code while preserving safe content. It functions as a utility for secure document object model manipulation, ensuring that user-provided rich text can be rendered safely within web applications. The library distinguishes itself through a single-pass, mutation-observer-free processing model that operates on detached document fragments to avoid triggering unintended side effects. It employs recursive node traversal and context-aware logic to inspect a

This repository serves as a comprehensive collection of reference implementations for the Remix web framework. It provides practical examples of full-stack web development, demonstrating how to build dynamic, server-rendered applications that bridge server-side logic with client-side interactivity. By leveraging a component-based architecture, these examples illustrate core patterns for managing data, routing, and user interfaces within a unified development environment. The collection highlights the framework's distinctive approach to web architecture, emphasizing server-side data loading an

Marshmallow is a Python data serialization library and validation framework. It functions as a bridge that transforms complex application objects into primitive data types for storage or network transmission and vice versa. The library utilizes a schema-based approach to validate that incoming data conforms to specific types and constraints. It employs a two-way transformation pipeline consisting of separate load and dump phases to handle deserialization and serialization. The framework supports class-based schema definitions with declarative field validation and recursive schema nesting for

This is a Go struct validation library used to maintain data integrity by enforcing constraints on fields, slices, and maps. It functions as a schema validation tool and data integrity validator, ensuring that complex nested structures adhere to predefined rules. The library utilizes struct tags to configure validation logic at runtime and supports a custom function registry for extending validation rules. It is distinguished by its ability to perform cross-field dependency evaluation, allowing the comparison of values between different fields within the same data structure to ensure logical

Templ is a type-safe HTML templating engine and UI framework for Go. It provides a system for building reusable HTML components that compile into Go code for server-side rendering, ensuring type safety and compile-time validation of data and logic. The project features a dedicated language server that provides autocomplete and syntax validation for template files within supported code editors. It employs compile-time code generation to transform a custom template language into Go source code, enabling the creation of modular HTML fragments and logic blocks. The framework includes automated s

react-markdown is a React renderer that converts markdown text into a virtual DOM to safely display formatted content. It functions as a markdown syntax parser and renderer that transforms markdown strings into structural elements, ensuring XSS-safe content delivery. The project allows for the mapping of standard markdown elements to custom React components for specialized styling and behavior. It supports syntax extensions through a plugin system, enabling additional formatting features such as tables, footnotes, and tasklists. The system includes security primitives for HTML and URL saniti

This library provides a collection of utilities for processing, validating, and formatting Brazilian personal data and national identifiers. It serves as a toolkit for managing common data formats within the Brazilian ecosystem, ensuring that information such as tax identification numbers, phone numbers, and postal codes conform to official standards. The project distinguishes itself by combining mathematical checksum verification with structural pattern matching to ensure data integrity. It includes specialized functions for generating synthetic, valid identification numbers for testing envi