30 open-source projects similar to sindresorhus/ow, ranked by shared indexed features. Tags may describe platforms or build tools rather than the same primary purpose. Check each project’s use case, license, and deployment requirements before treating it as a replacement.
Typia is a compile-time code generator that transforms TypeScript type annotations into runtime validation, serialization, and schema functions without requiring decorators or separate schema files. It generates optimized validation and serialization code during TypeScript compilation, producing dedicated functions for each type that eliminate runtime schema objects for faster execution. The project extends this core capability into several integrated areas. It generates fully typed client SDKs from NestJS controller source code, keeping server and client types synchronized automatically. It
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 library provides a comprehensive system for defining data schemas and enforcing structural integrity within JavaScript applications. It enables developers to construct declarative rules for complex, nested objects, ensuring that data conforms to expected types and constraints before it is processed or stored. By integrating directly with the Meteor framework, it serves as a central tool for maintaining consistent data structures across collections and remote procedure calls. The project distinguishes itself through its deep integration with reactive data systems, allowing validation stat
Go Package of validators and sanitizers for strings, numerics, slices and structs
Angular schema form is a framework directive and form component library that automatically generates and validates interactive HTML form controls from standard JSON schemas and companion layout configurations. It translates structured data definitions into customizable user input interfaces, parsing data types and custom rules into native form controls and reusable HTML markup templates. The project provides capabilities for dynamic field management, allowing form elements to show or hide conditionally by evaluating expressions against current model and scope state, and supporting dynamic arr
The php-standard-library is a comprehensive toolkit for functional programming and asynchronous networking in PHP, featuring typed data structures, structured concurrency, and composable validation mechanisms. It provides explicit result types and pure collection transformers that separate lists from dictionaries, eliminating traditional array key confusion and error-throwing patterns. The library supports concurrent execution through lightweight user-space fibers, message-passing channels, and non-blocking event loops, driving asynchronous TCP, TLS, UDP, and Unix socket servers without relyi
Luau is a high-performance programming language evolved from Lua 5.1. It consists of a bytecode virtual machine, an embeddable scripting engine, and a static code analyzer designed to provide a secure, sandboxed execution environment for host applications. The project is distinguished by its gradual typing system, which combines automatic type inference with optional manual annotations to detect bugs without requiring full static typing. It also features native vector mathematics for high-performance operations and a specialized debugging system that uses bytecode patching to minimize executi
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
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
ozzo-validation is a programmable data validation library for Go that verifies structs, maps, and primitive types using a declarative, rule-based approach. It functions as an interface-based validator, allowing for the recursive checking of nested data structures and custom types without the use of struct tags. The framework distinguishes itself as a context-aware validation engine, supporting the propagation of request-scoped data to rules that depend on external state. It provides extensive extensibility through custom rule definitions and the ability to override default failure text with l
This project is a static analysis engine and type checker designed for PHP codebases. It evaluates source code structure and type annotations to identify potential bugs, type mismatches, and logic errors without executing the application. By parsing code into an abstract syntax tree and applying a rule-based validation framework, it enforces code quality and safety standards across a project. What distinguishes this tool is its sophisticated type inference engine, which models dynamic language features, magic methods, and conditional types to maintain accuracy even in unconventional code. It
Valibot is a modular, type-safe schema library for validating and parsing structural data in TypeScript environments.
This project is a data validation framework for the Go programming language that enforces integrity by applying declarative constraints to struct fields. It utilizes reflection to inspect data structures at runtime, mapping field-level requirements defined in struct tags to specific validation logic. The library distinguishes itself through its ability to handle complex object graphs by recursively traversing nested structures and slices. It supports context-aware validation, allowing developers to switch between different rule sets for the same data structure based on application state or sp
Flasgger is a documentation framework for Flask applications that generates OpenAPI specifications and an integrated Swagger UI. It functions as a documentation generator and specification parser that extracts API schemas from route definitions, function docstrings, and external specification files. The tool allows API definitions to be maintained either within the source code using YAML blocks in docstrings or decoupled into standalone YAML files. It provides a browser-based interactive console for testing and exploring API endpoints directly from the web application. Beyond documentation,
TypeBox is a JSON schema generator and TypeScript data validator. It functions as a type builder that creates compliant JSON schema definitions while providing a mechanism for synchronizing runtime validation logic with compile-time types. The project allows for the automatic derivation of static TypeScript interfaces from schema definitions to eliminate redundant type declarations. It converts complex type constructs into schema fragments and resolves static types to maintain consistency between data shapes and code. The system covers runtime type checking and data validation through the us
Amber is a transpiler that translates high-level source code into executable shell scripts for Bash, Zsh, and Ksh. It provides a type-safe environment for shell script generation, allowing for static type validation and the creation of standalone executable scripts. The project distinguishes itself through a compilation process that includes tree-shaking import optimization to reduce output size and template-based script wrapping for custom headers and footers. It utilizes a module-based dependency resolution system with visibility controls to manage code reuse across multiple files. The lan
jscamp is a full-stack web development and education project focused on mastering JavaScript, TypeScript, and AI integration. It provides a structured curriculum and interactive exercises covering language fundamentals, frontend engineering, and backend API development. The project distinguishes itself through the implementation of autonomous AI agents capable of complex task automation, such as modifying files, managing servers, and executing API calls. It includes advanced AI development tools for conversational querying, real-time code suggestions, and automated repository analysis to gene
prop-types is a JavaScript object validator and runtime type checker. It serves as a development tool for verifying that object properties match predefined specifications, primarily used to ensure that data passed into React components aligns with expected types. The utility detects data inconsistencies by logging warnings to the console when mismatches occur, rather than throwing exceptions. It employs a stateful warning cache to prevent duplicate logs and restricts validation logic to non-production environments to avoid performance overhead in released builds. The project covers data vali
Flow is a JavaScript static type checker and AST parser that identifies type errors and prevents runtime failures through static annotations. It functions as a code intelligence engine and a static analysis linter to identify unsafe coding patterns and enforce consistency across a codebase. The project includes a type annotation stripper that removes static type signatures from source code, ensuring the resulting JavaScript is compatible with any runtime environment. It also provides a parser that converts typed JavaScript into an abstract syntax tree conforming to the ESTree specification.
TypeSpec is a language for defining cloud API shapes and generating OpenAPI, JSON Schema, and client/server code from a single source of truth. It functions as a protocol-agnostic API designer that models REST, gRPC, and other API protocols using a unified, extensible syntax, with a decorator-based metadata system for attaching metadata, validation rules, and lifecycle visibility to API models and operations. The compiler produces OpenAPI 3.0 specifications and other artifacts, and the tool supports declaring API versions and tracking changes to models, properties, and operations across releas
Respect/Validation is a PHP validation library that operates on single input values through a fluent, chainable rule system. Each validator instance builds a linear constraint pipeline by appending rules to an internal stack, executing them sequentially and short-circuiting on the first failure. The library captures validation failures as structured exceptions, enabling callers to inspect detailed error metadata programmatically and respond with meaningful messages. The library distinguishes itself through its exception-based error handling model, which provides programmatic access to validat
v8n is a JavaScript data validation library used to verify that values, objects, and arrays meet specific criteria. It functions as a schema-based validator and an asynchronous validation engine, utilizing a fluent API to construct sequences of chainable rules and constraints. The framework is distinguished by its ability to execute promises and network requests during the validation process to determine if a value is valid. It allows for the creation of reusable validation schemas and provides a customizable rule framework where users can define their own logic and configure how error result
Masuit.Tools is a comprehensive static utility library for .NET and ASP.NET Core development. It provides a broad collection of reusable helper methods and infrastructure components that cover common programming tasks without requiring dependency injection or instance management. The library is organized as flat utility classes, making its functionality directly accessible from anywhere in a project. The toolkit distinguishes itself through a wide range of integrated capabilities that go beyond typical utility libraries. It includes a multithreaded range-request file downloader with pause and
mypy is a static type checker for Python that analyzes source code to detect type errors and inconsistencies without executing the program. It functions as a static analysis tool and type inference engine, providing a gradual typing system that allows type hints to be added to a codebase incrementally while maintaining compatibility with dynamic typing. The project distinguishes itself through a combination of performance and precision features. It utilizes a daemon-based incremental checking system and multi-process parallel analysis to manage large codebases, supported by binary cache persi
Pytype is a static code analysis tool and type inference engine for Python. It functions as a static type analyzer that detects type mismatches and verifies type annotations without requiring full manual hinting, while also serving as a type stub generator for producing standalone definition files. The project distinguishes itself by automatically determining variable and function types through an analysis of code patterns and assignments. This inference engine allows for structural code verification and the generation of type stubs that describe the interfaces of modules and functions. The
This project is a comprehensive educational resource and programming course covering C++ language semantics and features from C++03 through C++26. It provides structured tutorials and technical guides focused on modern C++ development. The material offers specialized instruction on template metaprogramming, including the use of type traits and compile-time computations. It features detailed guides on concurrency and parallelism for multi-core execution, as well as a reference for software design applying SOLID principles and RAII. Additionally, it covers build performance optimization to redu
dlt is a Python data ingestion tool and ETL pipeline framework designed to fetch data from diverse sources and persist it into structured destinations. It functions as a schema inference engine that automatically detects data types and flattens nested JSON structures into relational tables, moving data from sources to lakehouses, warehouses, or vector databases. The project distinguishes itself through AI-powered pipeline generation, using large language models to scaffold extraction code and connectors for REST APIs. It also supports multimodal vector storage and specialized population of ve
Yup is a JavaScript schema validation library used to define data shapes and validate runtime values. It functions as an object schema validator and a data coercion engine, allowing developers to transform raw input values into desired types before performing validation checks. The library is distinguished by its support for dynamic schema validation, where rules can be adjusted at runtime based on sibling field values or external context. It also enables recursive data structuring for polymorphic fields and provides a system for extracting static TypeScript interfaces from runtime schema def
The Concise TypeScript Book: A Concise Guide to Effective Development in TypeScript. Free and Open Source.
This project is a comprehensive educational resource and programming guide for the TypeScript language. It serves as a manual for the type system and a reference for the language's core syntax, focusing on writing type-safe code and building scalable applications. The content provides detailed instruction on the TypeScript type system, covering interfaces, generics, and structural typing. It further acts as a compiler reference, analyzing how source code is transformed into an abstract syntax tree through scanning and parsing. The guide also covers software architecture design, detailing pro