jiter

0.13.0 verified Tue May 12 auth: no python install: verified quickstart: verified

jiter is a fast iterable JSON parser for Python, currently at version 0.13.0, released on February 2, 2026. It is actively maintained with a release cadence of approximately every 2-3 months.

pip install jiter

Common errors

error ModuleNotFoundError: No module named 'jiter' ↓

cause The 'jiter' package is not installed in the current Python environment or is not accessible to the running script.

fix

Install the package using pip: pip install jiter

error ERROR: Failed to build 'jiter' when installing build dependencies ↓

cause This error often occurs during installation when `pip` or `poetry` cannot compile the underlying Rust extension for 'jiter', possibly due to missing build tools (like Rust toolchain or C compiler) or environment-specific issues (e.g., specific Python versions or operating systems).

fix

Ensure you have the Rust toolchain installed (e.g., curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh). If using poetry, try poetry add jiter --build=venv or manually install with pip if the environment is complex. For some environments like Chaquopy, specific openai versions might resolve conflicts.

error ValueError: JSON input is incomplete ↓

cause The `jiter.from_json()` function was called with JSON bytes that are syntactically incomplete, and `partial_mode` was set to `False` (the default), which requires well-formed JSON.

fix

Provide complete and valid JSON bytes to jiter.from_json(), or set partial_mode=True to allow parsing of incomplete JSON and discard the trailing incomplete string, or partial_mode='trailing-strings' to include it. Example:

import jiter
# Fix: Provide complete JSON
complete_json = b'{"key": "value"}'
parsed_data = jiter.from_json(complete_json)

# Alternative: Allow partial JSON
partial_json = b'{"key": "incomplete st'
parsed_data_partial = jiter.from_json(partial_json, partial_mode=True)

error ValueError: Duplicate key found ↓

cause The `jiter.from_json()` function encountered a JSON object containing duplicate keys, and the `catch_duplicate_keys` option was set to `True`.

fix

Ensure the JSON input does not contain objects with duplicate keys, or set catch_duplicate_keys=False to allow jiter to silently handle (typically by using the last encountered value) duplicate keys. Example:

import jiter
# Fix: Remove duplicate key
valid_json = b'{"key1": "value1", "key2": "value2"}'
parsed_data = jiter.from_json(valid_json, catch_duplicate_keys=True)

# Alternative: Allow duplicate keys (last one wins by default if not caught)
duplicate_key_json = b'{"key": "value1", "key": "value2"}'
parsed_data_allowed = jiter.from_json(duplicate_key_json, catch_duplicate_keys=False)

Warnings

breaking In version 0.13.0, PyO3 was bumped to 0.28, which may require adjustments in Rust bindings if used. ↓

fix Update your Rust dependencies to be compatible with PyO3 0.28.

deprecated The 'jiter-pupy' package is a pure Python implementation of jiter and is no longer maintained. ↓

fix Use the official 'jiter' package for continued support and updates.

Install compatibility verified last tested: 2026-05-12

python os / libc status wheel install import disk

3.10 alpine (musl) - - 0.00s 19.1M

3.10 slim (glibc) - - 0.00s 19M

3.11 alpine (musl) - - 0.00s 20.9M

3.11 slim (glibc) - - 0.00s 21M

3.12 alpine (musl) - - 0.00s 12.8M

3.12 slim (glibc) - - 0.00s 13M

3.13 alpine (musl) - - 0.00s 12.4M

3.13 slim (glibc) - - 0.00s 12M

3.9 alpine (musl) - - 0.00s 18.6M

3.9 slim (glibc) - - 0.00s 19M

Imports

from_json
```
from jiter import from_json
```
Ensure correct import path to access the from_json function.

Quickstart verified last tested: 2026-04-23

A simple example demonstrating how to parse JSON data using jiter.

import os
from jiter import from_json

json_data = b'{"name": "John", "age": 30}'
parsed_data = from_json(json_data)
print(parsed_data)  # Output: {'name': 'John', 'age': 30}