Open-source alternatives to Fast Json Stringify

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

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

This library provides a procedural macro utility for Rust that automates the implementation of type-safe builder patterns. By leveraging the compiler to enforce structural integrity, it ensures that all mandatory fields are initialized and that objects are constructed in a valid state before the program executes. The project distinguishes itself by using typestate-based tracking and marker types to encode the initialization progress of an object directly into the type system. This approach allows for a zero-cost abstraction layer where all validation logic and state checks are resolved during

This project is a command-line schema-to-code converter designed to transform diverse data specifications into type-safe Python data structures. It functions as a generator for Pydantic models, dataclasses, and typed dictionaries, enabling developers to maintain synchronization between evolving data contracts and application code. By parsing formats such as JSON Schema, OpenAPI, AsyncAPI, Protobuf, and Avro, the tool automates the creation of native classes that reflect the constraints and metadata defined in the source specifications. The generator distinguishes itself through a highly confi

This project is a framework for the efficient serialization and deserialization of data structures. It provides a unified, macro-based interface that automates the conversion of complex internal objects into standardized formats and reconstructs them from raw input streams or buffers. By leveraging compile-time code generation, the library minimizes manual implementation overhead while ensuring consistent logic across diverse data types. The framework distinguishes itself through a format-agnostic data model and a visitor-based parsing architecture that decouples data structures from specific

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

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

go-json is a high-performance JSON serialization library for Go that serves as an encoder and decoder replacement for the standard library. It provides tools to convert native data structures to and from JSON format with optimized processing speeds. The library includes a conditional serializer for filtering specific data structure fields during the encoding process and a colorizer to produce color-coded JSON strings for human readability. The project supports context-aware marshaling to trigger specific logic during the serialization of complex data types.

easyjson is a high-performance JSON serializer and memory-optimized parser for Go. It provides a reflectionless code generator that creates static Go methods for marshaling and unmarshaling data, eliminating the need for runtime reflection to improve execution speed. The library reduces CPU and memory overhead through several optimization strategies. It employs a system of reusable memory buffer pools to minimize heap allocations and garbage collection pressure. Additionally, it utilizes string interning to deduplicate repeated values and zero-copy string referencing to point to existing buff

fastjson2 is a high-performance Java library used for serializing and deserializing Java objects to and from JSON strings and byte arrays. It functions as a binary JSON serializer for encoding objects into optimized binary formats to reduce payload size and increase processing speed. The project includes a JSONPath query engine for extracting specific data and fields from JSON documents using standardized path expressions and filters. It also serves as a JSON schema validator, providing utilities to generate data contracts and validate JSON input against defined schemas to ensure structural c

This project is a high-performance JSON library for Go, serving as a replacement for the standard encoding/json package. It provides a serialization engine for encoding and decoding data structures, alongside a schemaless parser for extracting specific values from JSON blobs using paths. The library distinguishes itself through a focus on reducing CPU and memory overhead. It implements a high-performance encoder that utilizes buffer reuse and reduced float precision to increase data throughput. Broad capability areas include data serialization, high-performance JSON processing, and schema-le

Boost is a collection of portable, high-performance source libraries that extend the C++ standard library. It provides a wide range of reusable components, data structures, and algorithms designed to add capabilities to the base language across different platforms. The project is distinguished by its extensive focus on compile-time template metaprogramming and generic programming. It implements advanced architectural patterns such as policy-based design, concept-based type validation, and the use of SFINAE for conditional template resolution to minimize runtime overhead. The library covers a

phpredis is a C-based native extension that bridges PHP applications with Redis servers for high-performance data storage and retrieval. It serves as an interface for manipulating strings, hashes, lists, sets, and sorted sets while providing a direct path for executing Redis commands and server-side scripts. The extension provides comprehensive support for distributed environments and high availability. It interfaces with Redis Cluster to distribute data across multiple nodes using hash slots and manages Redis Sentinel for service discovery and automatic failover. It also enables shared state

This project is a JSON Schema validation library and framework used to verify that data instances conform to declarative definitions. It functions as a validation engine that enforces structural constraints and data types, while also serving as a meta-validator to ensure schema definitions themselves are syntactically correct against official meta-schemas. The library is designed for extensibility, allowing users to define custom validation logic by mapping schema keywords to specialized callable functions. It includes a registry-based reference resolver for managing internal and external URI

Superjson is a lossless JSON serialization library and data transcoder. It converts complex JavaScript and TypeScript data types into strings and metadata to ensure that type identity is preserved during data transfer. The library preserves non-native types such as Dates, Maps, and Sets by splitting values into a JSON-compatible payload and a separate map of type-specific metadata. It utilizes a registry-based mapping system that allows for the definition of custom type handlers to manage third-party data types during serialization and deserialization. This utility supports cross-process dat

This library is a Java-based tool for enforcing data structure constraints and verifying technical formats against defined schema specifications. It functions as a processing utility that parses complex data structures while managing external schema references and circular dependencies. The engine distinguishes itself through an immutable processor design that enables thread-safe, concurrent validation without requiring external synchronization. It employs arbitrary-precision arithmetic to evaluate numeric constraints, preventing common floating-point rounding errors, and utilizes character-l

MagicOnion is a remote procedure call framework for the .NET platform and Unity. It functions as a binary API protocol and real-time communication engine that uses shared interfaces to provide type-safe communication between clients and servers. The framework distinguishes itself through its compatibility with ahead-of-time compilation environments, utilizing source generators for client proxies and serialization to support mobile and console platforms including those using IL2CPP. It provides a specialized middleware layer for Unity that handles engine-specific data types and ensures runtime

RON is a serializer and deserializer for a strongly typed, human-readable data exchange format. It mirrors Rust language syntax to represent complex data structures and configurations, serving as an alternative to formats like JSON and TOML. The format preserves native Rust type idioms, including enums, structs, tuples, and ranges. It supports inline comments and specialized numeric bases, allowing for the creation of typed configuration files and human-editable data storage. The library provides source-mapped error reporting to track character coordinates during syntax failures and includes

Comlink is a remote procedure call library that transforms message-based communication into asynchronous function calls between the main thread and web workers. It provides a proxy-based interface that allows multiple threads to interact with a single object instance without manual message handling. The project enables the execution of functions across separate browser windows, iframes, and web workers, making external calls behave like local asynchronous operations. It supports the transfer of non-cloneable data through custom serialization handlers and allows for the movement of ownership f

JSONExport is a multi-language code generator and JSON schema converter that transforms JSON data structures into strongly typed source code classes. It serves as an API response mapper, converting JSON objects into data transfer objects to automate the creation of model classes. The tool specializes in multi-language model synthesis, allowing users to define data models across different programming languages using a single JSON input. It generates class boilerplate, including constructors and accessors, and provides a preview pipeline to review the resulting source code before it is saved.

This project is a Python implementation of the JSON Schema specification, providing a library for verifying that data instances conform to defined schemas. It serves as a data validation framework capable of validating both the data itself and the schemas against official meta-schemas to ensure structural correctness. The library features a schema reference resolver that maps URIs to definitions, enabling the resolution of internal and remote references for modular schema management. It is designed for extensibility, allowing for the definition of custom keywords, custom type-checking logic,

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

cppformat is a type-safe C++ formatting library that serves as a high-performance alternative to standard C++ input and output streams for converting data into formatted strings. It integrates a compile-time format validator to ensure format specifiers match argument types, preventing runtime crashes. The library includes a positional argument engine that enables the reordering of text arguments for internationalization and localization. It also features a Unicode text formatter to ensure consistent and portable character representation across different operating systems. The project provide

threads.js is a JavaScript worker thread library and asynchronous task orchestrator designed to offload CPU-intensive tasks to background threads. It functions as a cross-platform worker pool and a TypeScript worker runner that automatically transpiles and executes TypeScript files within separate threads. The project distinguishes itself by providing a unified worker API that allows for cross-platform execution across different JavaScript environments. It includes a specialized worker data serialization tool to pass complex class instances and binary data between threads, and supports inlini

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

Murder is an entity component system game engine designed for 2D game development. It provides a core framework for managing game objects through an ECS architecture and includes a dedicated 2D game editor for asset management and real-time property configuration. The engine features a specialized 2D rendering pipeline supporting pixel art, sprite slicing, and parallax effects. It includes a hierarchical A* pathfinding system for agent navigation and a comprehensive asset management system for serializing and loading game resources. The project covers a broad range of capabilities, including

localForage is a browser storage wrapper and key-value store that provides a unified JavaScript API for persisting data. It acts as an abstraction layer over IndexedDB, WebSQL, and localStorage, allowing web applications to save data offline. The library features a priority-based driver fallback system that automatically detects and selects the most capable storage engine available in the browser. It simplifies data management by providing an asynchronous interface for storing complex JavaScript objects and binary buffers without requiring manual serialization. The project covers broad capab