Crate serde_json_core[][src]

serde-json for no_std programs

This version of serde-json is aimed at applications that run on resource constrained devices.

Current features

  • The error type is a simple C like enum (less overhead, smaller memory footprint)
  • (De)serialization doesn’t require memory allocations
  • Deserialization of integers doesn’t go through u64; instead the string is directly parsed into the requested integer type. This avoids pulling in KBs of compiler intrinsics when targeting a non 64-bit architecture.
  • Supports deserialization of:
    • bool
    • Integers
    • str (This is a zero copy operation.) (*)
    • Option
    • Arrays
    • Tuples
    • Structs
    • C like enums
  • Supports serialization (compact format only) of:
    • bool
    • Integers
    • str (**)
    • Option
    • Arrays
    • Tuples
    • Structs
    • C like enums

(*) Deserialization of strings ignores escaped sequences. Escaped sequences might be supported in the future using a different Serializer as this operation is not zero copy.

(**) Serialization of strings doesn’t escape stuff. This simply has not been implemented yet.

Planned features

  • (De)serialization from / into IO objects once core::io::{Read,Write} becomes a thing.


This is explicitly out of scope

  • Anything that involves dynamic memory allocation
    • Like the dynamic Value type

Minimum Supported Rust Version (MSRV)

This crate is guaranteed to compile on stable Rust 1.51.0 and up. It might compile with older versions but that may change in any new patch release.


pub use self::ser::to_string;
pub use self::ser::to_vec;
pub use heapless;



Deserialize JSON data to a Rust data structure


Serialize a Rust data structure into JSON data



Deserializes an instance of type T from bytes of JSON text Returns the value and the number of bytes consumed in the process


Deserializes an instance of type T from a string of JSON text


Serializes the given data structure as a JSON byte vector into the provided buffer