Open-source alternatives to Json Schema Validator

This project is a Java library designed to validate JSON documents against defined schema specifications. It functions as a standards-compliant engine that ensures data integrity by checking structural compliance and enforcing business rules within Java applications. The library distinguishes itself through its flexible validation strategies, allowing developers to inject custom logic and pattern-matching engines to handle specialized data formats. It supports configurable execution modes, enabling users to either halt validation immediately upon the first error or collect all violations for

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

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

CUE is a constraint-based configuration language designed for data validation, schema definition, and code generation. At its core, it unifies types and values into a single concept, enabling compile-time validation that catches structural and value errors before runtime. The language treats data and constraints as the same thing, allowing a single definition to serve as both a schema and concrete configuration data. CUE distinguishes itself through its constraint-based unification engine, which combines multiple configuration sources into a single coherent result by merging their constraints

JSON Editor is a schema-driven UI framework and web-based editor used to generate interactive forms and validate JSON data. It translates JSON Schema specifications into a hierarchy of HTML form elements, allowing users to manipulate complex JSON structures through a structured interface rather than raw text. The framework differentiates itself through a plugin-based extension system that supports custom resolver functions and the integration of specialized editors, such as WYSIWYG, Markdown, and syntax-highlighted code editors. It employs recursive schema resolution to handle nested definiti

Carbon is a date and time manipulation library for PHP that extends the native DateTime class. It provides a set of tools for calculating, formatting, and comparing dates and times using a simplified, human-readable syntax. The library utilizes a fluent interface and static factory methods to allow for chained method calls and intuitive object instantiation. It supports both mutable and immutable state options to manage how date objects are modified and returned. The toolset covers temporal data management, including time zone handling and localization-based formatting to convert date compon

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

1loc is a JavaScript utility library and multifaceted toolkit providing a collection of single-line functions for common mathematical, string, date, and geometric operations. It functions as a set of functional programming helpers and data validation predicates designed to perform atomic transformations and validations. The project includes a geometry math library for calculating distances, angles, and spatial overlaps between points and rectangles, alongside a text manipulation library for casting, capitalizing, and analyzing string content. The toolkit covers broader capability areas inclu

Hazelcast is a distributed data platform that combines an in-memory data grid with a stream processing engine to support real-time analytics and event-driven applications. It functions as a partitioned, distributed key-value store that replicates data across cluster nodes to provide low-latency access and high availability. The platform also serves as a distributed SQL query engine, allowing users to execute standard SQL statements against both in-memory datasets and external data sources. What distinguishes Hazelcast is its use of a distributed consensus subsystem to maintain strongly consis

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

Valibot is a modular, type-safe schema library for validating and parsing structural data in TypeScript environments.

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

This project is a collection of curated guidelines and manuals for writing clean, idiomatic, and maintainable code in Scala. It serves as a comprehensive guide for Scala coding standards, functional programming design, and enterprise software architecture. The repository provides specific strategies for concurrency management, including patterns for actors, futures, and thread pools to ensure thread safety. It also contains a performance optimization manual focused on reducing memory allocations and managing garbage collection pressure to improve runtime efficiency. The guides cover a broad

Lancet is a comprehensive extension of the Go standard library, providing a collection of reusable functions and data structures designed to reduce boilerplate code in applications. It serves as a general-purpose toolkit across multiple domains, including concurrency, security, networking, and functional logic. The project distinguishes itself through specialized toolkits for Go concurrency, such as keyed locking and channel-based stream processing, and a dedicated functional programming kit that supports currying and function composition. It also includes a dedicated cryptography library imp

Ajv is a JSON Schema validator and schema compilation engine used to verify that JavaScript objects conform to specific JSON Schema definitions. It functions as a data coercer and localization tool, allowing for the application of default values and the translation of validation error messages into different languages. The project converts declarative JSON Schema definitions into optimized JavaScript functions to increase validation speed. It supports the extension of validation logic through custom keywords and the generation of standalone validation code that executes without external depen

node-fs-extra is a Node.js file system extension that provides a set of additional methods to simplify common file and directory operations. It functions as a recursive directory manager, a JSON file processor, and a file asset manipulator, extending the standard library to provide high-level utilities for managing assets on disk. The project distinguishes itself through recursive capabilities, such as duplicating or removing nested folder structures and ensuring that all missing parent directories are automatically generated when creating files or symbolic links. It also integrates a JSON se

Objection.js is an object-relational mapper for Node.js that maps SQL database tables to classes and rows to model instances. It functions as a high-level abstraction layer built on top of the Knex.js query builder to provide structured model definitions and relational data mapping. The project distinguishes itself through its ability to manage complex object graphs, allowing for the persistence and eager-loading of deeply nested related data in single operations. It incorporates a data integrity layer that uses JSON schema validation to verify model instances before they are persisted to the

Spectral is a programmable linting engine and validation tool designed to enforce style guidelines and schema correctness within OpenAPI specifications and JSON configuration files. It functions as a rule-based validator that analyzes structured text files to ensure data consistency and adherence to predefined constraints. The engine utilizes a configuration-driven execution model, allowing users to manage pluggable rule sets and integrate JSON Schema definitions. It supports the creation of custom function-based rules to define complex validation logic beyond static declarations. The projec

HackMyResume is a command-line tool that generates polished résumés and CVs in multiple formats from a single JSON or YAML data source. It validates résumé documents against the FRESH or JSON Resume schema, converts between these two formats, and produces output in HTML, Markdown, LaTeX, MS Word, PDF, plain text, JSON, XML, and YAML. The tool supports custom themes through a plugin architecture, allowing users to apply visual styling via Handlebars templates and register custom helpers for extended template logic. It can merge multiple résumé JSON files into one, overriding generic data with

ts-essentials is a comprehensive toolkit of utility types and libraries for TypeScript, providing advanced primitives for recursive structural transformations, runtime assertions, and type guards. It serves as a utility library for performing complex type-level programming to ensure stronger type safety and reduce boilerplate. The project distinguishes itself through a specialized set of tools for deep object manipulation, such as recursively applying read-only or optional modifiers across nested hierarchies. It also provides a dedicated set of strict type constraints to ensure data structure

The WordPress REST API is a web interface and JSON-based content API that allows for the retrieval and modification of site content, users, and metadata using standard HTTP methods. It functions as a headless CMS interface, decoupling content management from the frontend by exposing site data through a programmable RESTful controller. The system is distinguished by its hypermedia-driven discovery and JSON-schema-based validation, which allow clients to programmatically locate resources and ensure predictable data exchange. It utilizes namespace-based endpoint registration to organize routes a

AWS Powertools for Python is a utility framework designed for building production-ready Python functions on AWS Lambda. It provides a comprehensive suite of tools for observability, event parsing, routing, and idempotency management to streamline the development of serverless applications. The project distinguishes itself through specialized capabilities for event-driven architectures and AI agent orchestration. It enables the implementation of AI agents by exposing functions as tools via OpenAPI schemas and managing conversation states. Additionally, it features an idempotency library that p

Kinto is a cloud state backend designed for storing and synchronizing JSON data across multiple devices. It provides a centralized service for managing schema-less JSON records organized into buckets and collections, ensuring a consistent state through a REST API. The system supports collaborative data sharing by granting read and write access to specific documents or collections via user groups and permissions. It enables document synchronization using change feed tracking and deletion markers to update clients with the latest state. Capabilities include fine-grained access control, JSON sc

mcpo is a gateway and router that converts Model Context Protocol tools into standard REST API endpoints. It functions as a validation proxy and security layer, mapping multiple tool server configurations to unique URL paths while using standardized schema definitions to validate input parameters and output formats. The project implements an OAuth security layer using dynamic client registration to verify identities via an authentication server. It also acts as a bridge for reverse proxies by applying configurable base paths to internal endpoints, ensuring compatibility with network load bala

This project provides a standardized data format for representing professional work history and skills using structured objects. It serves as a formal specification for verifying that career information conforms to required fields and structural constraints, ensuring consistent representation across digital platforms and services. By decoupling raw professional information from its visual presentation, the schema enables the programmatic generation of resumes in multiple formats from a single source. This approach allows for the creation of machine-readable files that can be parsed and render

SchemaStore is a centralized JSON schema registry and configuration validation service. It serves as a searchable catalog of standardized JSON definitions used to verify that configuration files adhere to predefined structural rules and data types. The project functions as an autocomplete provider, suggesting available keys and valid values for configuration files during the editing process. It employs a remote directory of schemas indexed by file path and pattern to provide a single source of truth for validation and autocompletion in text editors. The system covers automated configuration

Joda-Time is a Java date and time library and framework used for parsing, representing, and calculating temporal data. It provides a thread-safe temporal API that uses immutable objects to ensure concurrency safety and adheres to the ISO8601 standard. The project is distinguished by its pluggable calendar system, which supports diverse chronologies including Gregorian, Buddhist, Coptic, Ethiopic, and Islamic calendars. It also functions as a time zone management tool, utilizing an internal IANA-based zone database to translate instants and update daylight savings rules independently of the ho