Sonic is a JSON serialization and deserialization library for Go that uses just-in-time compilation and SIMD instructions to accelerate performance.
The library addresses the need for fast JSON processing by combining JIT compilation with SIMD operations to speed up both encoding and decoding. It provides runtime object binding without requiring code generation, complete APIs for JSON value manipulation, and streaming IO support for handling multiple values while reducing memory consumption. The tool maintains API compatibility with Go's standard encoding/json library in most cases, though it differs in HTML escaping behavior and optional key sorting features.
Developers should choose Sonic if their Go applications require high-performance JSON processing across small, medium, and large payloads. The library suits projects where JSON throughput is a bottleneck, particularly those handling substantial data volumes. It works on Linux, macOS, and Windows with support for AMD64 processors and ARM64 on Go 1.20 and above. The tool requires Go 1.18 or higher, though Go 1.24.0 has a known incompatibility that can be worked around with a build flag.
The project maintains active development with regular updates addressing edge cases and adding refinements. The maintainers have added specific error handling for mismatched types in JSON values, allowing decoding to continue while reporting problems. The tool includes a self-contained AST implementation for JSON that supports both serialization and deserialization with APIs for querying and modifying generic data. Performance optimizations are deliberately selective, with features like key sorting and HTML escaping disabled by default due to their performance cost, though both remain available as optional settings.
