jsonyx 2.0.0.post1

Customizable JSON library for Python

jsonyx

jsonyx is a customizable JSON library for Python 3.8+. It is written in pure Python with an optional C extension for better performance and no dependencies.

The documentation for jsonyx is available online at: https://jsonyx.readthedocs.io

Key Features

• JSON decoding, encoding and patching
• Pretty printing:

  {
      "foo": [1, 2, 3],
      "bar": {"a": 1, "b": 2, "c": 3}
  }
  

• Optionally supports these JSON deviations (specified in the documentation):

  {
      /* Block */ // and line comments
      "Missing commas": [1 2 3],
      "NaN and infinity": [NaN, Infinity, -Infinity],
      "Surrogates": "\ud800",
      "Trailing comma": [0,],
      "Unquoted keys": {key: "value"}
  }
  

• Detailed error messages:

  Traceback (most recent call last):
    File "/Users/wannes/Downloads/broken.json", line 1, column 99-381
      ...sList": {"GlossEntry": {"ID": "SGM..."GML", "XML"]}, "GlossSee": "markup"
                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  jsonyx.JSONSyntaxError: Unterminated object
  

• Dedicated functions for reading and writing files and pretty printing

Benchmark (Mar 17, 2025)

We recommend to use orjson, msgspec or pysimdjson for performance critical applications:

encode	json	jsonyx	msgspec	orjson	fastest time
List of 256 booleans	4.69x	5.64x	1.00x	1.04x	1.92 μs
List of 256 ASCII strings	13.08x	15.03x	1.62x	1.00x	3.67 μs
List of 256 floats	24.38x	24.69x	1.35x	1.00x	7.89 μs
List of 256 dicts with 1 int	11.34x	14.32x	1.35x	1.00x	7.67 μs
Medium complex object	10.64x	12.05x	1.15x	1.00x	13.38 μs
List of 256 strings	21.28x	15.85x	1.95x	1.00x	15.16 μs
Complex object	7.14x	7.65x	1.00x	DNF[^1]	213.74 μs
Dict with 256 lists of 256 dicts with 1 int	9.03x	11.34x	1.14x	1.00x	2423.70 μs

decode	json	jsonyx	msgspec	orjson	simdjson	fastest time
List of 256 booleans	4.65x	7.19x	3.02x	1.41x	1.00x	1.43 μs
List of 256 ASCII strings	7.35x	12.65x	4.73x	4.42x	1.00x	2.98 μs
List of 256 floats	10.85x	12.17x	2.16x	1.66x	1.00x	6.10 μs
List of 256 dicts with 1 int	13.56x	16.11x	6.92x	5.24x	1.00x	6.17 μs
Medium complex object	12.47x	18.84x	5.25x	4.34x	1.00x	7.68 μs
List of 256 strings	4.01x	3.41x	14.99x	8.04x	1.00x	23.47 μs
Complex object	8.92x	7.75x	9.09x	9.16x	1.00x	145.17 μs
Dict with 256 lists of 256 dicts with 1 int	17.95x	22.36x	12.42x	10.53x	1.00x	1621.17 μs

[!WARNING] The Python version of jsonyx is up to 36.25x slower, so make sure you have a C compiler installed on Windows.

[^1]: failed due to recursion error