Open-source alternatives to Jsonparser

This is a Rust serialization library for converting data structures to and from JSON strings and byte streams. It is built as a framework within the Serde ecosystem, providing both a strongly typed parser for compile-time safety and a recursive value tree for manipulating JSON data without a predefined schema. The project supports both typed and untyped processing. It can map JSON data into specific Rust types for schema conformity or parse input into a flexible, schemaless representation. It also includes macro-based utilities for the dynamic construction of JSON objects.

This is an educational tutorial that walks through implementing a complete JSON library from scratch in C. The project covers the full data lifecycle of JSON, including parsing text into structured in-memory representations, validating input against the specification, serializing data back into standard JSON output, and providing structured access to elements within parsed arrays and objects. The implementation is built around a hand-written recursive descent parser that processes JSON text by matching grammar rules to build a structured data tree. Parsed values are stored in a tagged union r

cJSON is a lightweight library for parsing, creating, and modifying JSON data structures within C applications. It provides a comprehensive set of utilities for transforming raw text into navigable objects, manipulating data fields within collections, and serializing complex structures into formatted or unformatted strings. The library is designed for memory-sensitive and resource-constrained environments, utilizing manual memory management and type-tagged union structures to maintain a minimal footprint. It employs recursive descent parsing and in-place string manipulation to process data ef

RapidJSON is a header-only C++ library designed for high-performance parsing, generation, and manipulation of JSON data. It functions as a dual-mode engine, providing both an in-memory document object model for tree-based manipulation and a stream-based interface for event-driven processing. The library is built to minimize memory footprint and maximize execution speed, making it suitable for resource-constrained environments. The library distinguishes itself through advanced memory management and optimization techniques, including in-situ parsing that modifies input buffers directly to elimi

JSONKit is an Objective-C library used for parsing, serializing, and manipulating JSON data. It functions as a JSON parser that converts text into native data structures and a serializer that transforms native objects into formatted JSON text. The library includes a gzip compression wrapper that compresses serialized JSON payloads to reduce network transfer sizes and automatically detects and decompresses gzip buffers before decoding. The toolset provides capabilities for JSON parsing and serialization, supporting customizable indentation, character escaping, and flexible comment handling.

Moshi is a JSON serialization library and parser for Kotlin and Java. It functions as a reflectionless JSON encoder that converts typed objects to JSON strings and parses JSON data back into language objects. The library distinguishes itself through compile-time adapter generation, which removes the performance overhead associated with runtime reflection. It also provides a polymorphic JSON mapper that uses type identifiers to resolve and instantiate specific subclasses of a common base type. The framework supports custom adapter definitions for specialized type conversion, including nullabi

Ultrajson is a high-performance Python JSON library and C-based parser designed to minimize parsing overhead. It provides a C implementation of the JSON specification to enable fast encoding and decoding of data. The project functions as a concurrent JSON processor, supporting multi-threaded serialization and deserialization to increase data throughput and prevent blocking execution. Its capabilities cover Python data serialization and high-performance JSON processing for real-time data pipelines. This includes parsing JSON data and serializing native objects into JSON strings.

jid is an interactive JSON query tool and data explorer for the terminal. It provides a keyboard-driven interface to navigate, evaluate, and extract information from nested JSON structures using dot-notation paths and real-time autocomplete. The tool integrates JMESPath to support complex data filtering and transformation. It distinguishes itself through a type-aware assistance system that provides context-aware function hints and argument templates based on the data type of the selected JSON node. The capability surface includes a terminal user interface with syntax highlighting, predictive

simdjson is a high-performance JSON parser that utilizes SIMD instructions to process gigabytes of data per second. It functions as a SIMD JSON parser, a multithreaded NDJSON processing library, a UTF-8 validation engine, and a tool for JSON minification and string building. The project focuses on high-throughput data processing, enabling the ingestion of massive JSON volumes and the verification of UTF-8 encoding standards. It includes dedicated capabilities for constructing JSON strings with optimized memory usage and removing unnecessary whitespace from documents to reduce file size. The

JsonCpp is a C++ library for parsing, manipulating, and generating JSON data. It functions as a data interchange tool that provides a JSON parser to convert formatted text into structured data and a JSON serializer to transform internal data structures back into valid JSON strings. The library features the ability to preserve non-standard JSON comments during the deserialization and serialization process, which supports the management of human-readable configuration files. The project implements a tree-based internal representation for programmatic data access and uses a builder-based config

Fastjson is a Java data binding framework and serialization library designed to convert objects to JSON strings and parse JSON data into typed objects. It functions as a JSON parser and stream processor capable of transforming JSON strings into data structures. The project emphasizes high performance JSON processing and memory management, specifically through the use of a pipeline to stream oversized JSON objects and texts to prevent memory exhaustion. It provides capabilities for JSON data serialization and deserialization workflows, including custom JSON data mapping and the ability to def

jsmn is a lightweight JSON parser library written in C. It provides zero-copy tokenization and incremental parsing designed for use in embedded systems and memory-constrained environments. The library identifies structural JSON elements by providing offsets into the original string rather than allocating new memory for data. It uses a single-pass scanning method and requires static-buffer allocation, meaning the caller provides the memory for tokens to avoid dynamic allocation during the parsing process. The parser supports incremental streaming, allowing it to process JSON data in chunks fr

ArduinoJson is a C++ library for parsing and manipulating JSON data and MessagePack binary streams on microcontrollers with limited memory and processing power. It provides the core primitives necessary for embedded data serialization and parsing, enabling devices to exchange structured data over serial or network interfaces. The library is distinguished by its focus on microcontroller memory management, employing strategies such as pool-based allocation, string deduplication, and non-owning string views to minimize RAM usage. It further optimizes for constrained environments by allowing cons

JsonPath is a Java library designed for querying and manipulating JSON documents using the JsonPath expression language. It functions as a query engine for extracting and filtering specific data from JSON structures through path-based expressions. The library provides capabilities for transforming JSON documents by modifying values or mapping extracted data into Java objects. It also includes an aggregation library for calculating statistical metrics, such as sums and averages, on numeric arrays. The project handles data extraction through array filtering and numerical aggregation. Performan

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

Sonic is a high-performance Go JSON serialization library that provides tools for encoding and decoding native data structures. It functions as a JIT-accelerated encoder, a JSON AST parser, a stream processor, and a lazy decoder. The project utilizes just-in-time machine code generation to optimize the encoding of large data schemas and employs a JIT assembler to maximize serialization and deserialization speeds. It features a precompiled schema warmup process to prevent latency spikes during initial execution and leverages SIMD hardware instructions for accelerated parsing. The library cove

RapidJSON is a high-performance C++ library used for parsing and generating JSON data. It provides both document object model and stream-based interfaces to transform JSON strings into structured data and vice versa. The library includes a JSON schema validator to verify that documents conform to predefined rules and a Unicode transcoder for converting strings between UTF-8, UTF-16, and UTF-32 encodings. It also supports relaxed parsing for non-standard JSON containing comments or trailing commas. Additional capabilities cover JSON pointer navigation for locating specific values and string s

This is an asynchronous HTTP client for Android that simplifies network requests by wrapping Apache HttpClient. It provides a callback-based networking library for fetching remote data and communicating with servers without blocking the user interface. The project includes a multipart HTTP uploader for sending binary files and large data payloads, as well as a JSON parser to convert raw response text into structured data objects. It features a session manager that persists cookies in local application preferences to maintain state across multiple requests. Additional capabilities include aut

The C++ REST SDK is a library for asynchronous HTTP and RESTful communication in native C++ applications. It provides a non-blocking network client for sending requests and receiving responses, a JSON parser for serializing and deserializing data, and a WebSocket client library for real-time, full-duplex communication. The project includes a dedicated OAuth2 authentication client to manage access tokens and authorization flows for secure communication with protected cloud resources. It utilizes a task-based asynchronous model to coordinate background operations and keep application interfaces

orjson is a high-performance Python library for serializing and deserializing JSON data. It functions as both a JSON parsing library and a serialization engine, converting data between native Python objects and UTF-8 encoded bytes. The project provides specialized support for converting complex Python data structures, including dataclasses, datetime objects, and NumPy arrays and scalars, into JSON format. It also allows for the insertion of pre-serialized JSON blobs into documents to maintain processing speed. The library includes capabilities for memory-efficient deserialization through key

body-parser is a Node.js HTTP request parser that converts incoming request bodies into structured JavaScript objects. It provides utilities to extract and process JSON, raw binary, plain text, and URL-encoded payloads for use in web servers. The project employs a middleware pattern to augment request objects, attaching parsed data directly to the request for use in subsequent route handlers. It uses content-type based dispatching to select the appropriate parsing logic based on the request headers. The tool manages data streams by consuming payloads in chunks and accumulating binary buffers

This is a JavaScript library for parsing and serializing JSON data, with a particular focus on handling objects that contain circular references. It provides a standard JSON parser that reads text and reconstructs JavaScript values without using the eval function, guarding against code injection, alongside a standard serializer that converts objects into JSON strings for data interchange. The library distinguishes itself by offering specialized encoding and decoding for cyclical object graphs. It can serialize objects with circular references by replacing repeated object paths with JSONPath s

UltraJSON is a high-performance JSON library and parser written in C with bindings for Python. It provides a fast alternative to standard JSON processing for decoding JSON strings into native data structures and encoding data structures back into JSON strings. The library utilizes a C-based engine to reduce processing latency and increase throughput for JSON generation and parsing. It is designed to accelerate data pipelines and optimize the handling of JSON payloads.

http-parser is a C-based library for extracting request and response metadata from raw HTTP data streams. It utilizes a state-machine approach to identify message segments and boundaries. The project implements zero-copy string parsing and pointer-based URL deconstruction to avoid memory allocations and data duplication. It supports incremental stream processing to handle fragmented data chunks and includes mechanisms for decoding chunked encoding and managing network protocol upgrades.

jless is an interactive JSON explorer and command-line viewer designed for reading and navigating hierarchical data structures within a terminal. It functions as a terminal JSON formatter that pretty-prints data from files or standard input, including support for newline-delimited formats. The tool serves as a JSON path extractor, allowing users to identify and copy the dot or bracket notation paths from the root to specific nodes. It also includes a regex search utility for locating specific keys and values within JSON datasets using full-text regular expressions. The application provides c

RedisJSON is a system for storing and managing JSON data within Redis using a native binary format. It enables the storage of JSON documents and the retrieval of nested data using targeted path syntax. The project provides the ability to perform atomic updates on individual elements within a nested JSON object, allowing for modifications without retrieving and rewriting the entire document. It further supports NoSQL data indexing by creating secondary indexes on specific fields to accelerate search and filtering operations across datasets. Its broader capabilities cover hierarchical data ret

nom is a parser combinator framework for Rust used to build complex parsers by combining small, reusable parsing functions. It functions as a zero-copy parsing tool that minimizes memory overhead by returning slices of the original input instead of allocating new memory. The framework is designed for diverse data formats, serving as a binary data parser with configurable endianness and a bitstream processing library capable of extracting values of arbitrary bit length. It also functions as a streaming data parser that can process data arriving in chunks and signal when additional input is req