Fast JSON parser and validator for Go. No custom structs, no code generation, no reflection (by valyala)

Fastjson Alternatives

Similar projects and alternatives to fastjson

NOTE: The number of mentions on this list indicates mentions on common posts plus user suggested alternatives. Hence, a higher number means a better fastjson alternative or higher similarity.

fastjson reviews and mentions

Posts with mentions or reviews of fastjson. We have used some of these posts to build our list of alternatives and similar projects. The last one was on 2023-06-29.
  • What's the best way to unmarshall this nested JSON?
    3 projects | /r/golang | 29 Jun 2023
    I’ve used fastjson when unmarshalling to Structs is inconvenient.
  • Object-oriented JSON in Go
    2 projects | /r/golang | 12 Apr 2023
    Interesting approach, even though reflection support is supposed to be landing soon, this would be really really useful when using TinyGo. (Fro example, writing web backend serverless functions with Fermyon’s Spin framework for WASM that needs to return JSON). Do you have any benchmarks on how it performs vs stdlib’s encoding/json and/or something like fastjson?
  • Best approach for a monolithic web app?
    2 projects | /r/golang | 9 Apr 2023
  • High-performance JSON parsing in Go
    4 projects | /r/golang | 8 Mar 2023
    FastJason ( does not use code generation or structs and is great for parsing very dynamic schemas.
    4 projects | /r/golang | 8 Mar 2023
    It relies heavily on bytes.IndexOf for which Go provides SIMD optimizations transparently. However, it has some correctness issues when parsing malformed json that might need to be addressed. Generally it is recommended to be used with trusted json documents for internal services and may require further testing before being used to parse arbitrary json documents.
  • 3 Ways I Keep My Rest APIs endpoints down to 4-6 lines and eliminate boilerplate. What are yours?
    3 projects | /r/golang | 4 Mar 2023
    Try fastjson library. It allows you to grab deeply nested json objects without marshalling the entire json.
  • Any way to convert unknown/dynamic json to generic object structure
    3 projects | /r/golang | 2 Mar 2023
  • Golang, GraphQL y Postgress
    2 projects | /r/devsarg | 26 Jan 2023
    Como herramientas te recomiendo: FastJson : Si necesitas leer jsons Testify : Para mockear y testear
  • Ad hoc JSON parsing
    4 projects | /r/golang | 16 Jan 2023
    In Go if I need to extract just a few fields from a large JSON document it's hard to beat
  • TinyGo Reflection?
    4 projects | /r/golang | 6 Dec 2022
    Another option is to use what I like to call "Lazy" decoders, like which will work with TinyGo, but doesn't have the same type of API as the standard lib (or alternatives) in terms of Marshaling and Unmarshalling. Instead you "Parse" a JSON object, and use Getters to access the types you want.
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Basic fastjson repo stats
3 months ago
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