PyPI · #92 most downloaded on PyPI

jiter

0.17.0313M downloads/mopydantic/jiter ↗New releases in your daily digest, changelog included.

Fast iterable JSON parser.

Last release 22 days ago
12 Sep 2026
Ships fairly regularly
a new release about every 2 months
Nearly every release is documented
notes for 22 of 22 stable releases
Nothing withdrawn
no release was ever pulled
2 years old
22 releases · first in 2024

Release timeline

22 releases since 2024

202420252026

Releases

0.17.012 Sept 2026
Commit Cargo.lock so benchmarks aren't subject to dependency drift by @samuelcolvin in #265
What's Changed

Commit Cargo.lock so benchmarks aren't subject to dependency drift by @samuelcolvin in #265

add unicode dense benchmark by @samuelcolvin in #264

SIMD refactor by @samuelcolvin in #263

Compare jiter with serde_json over the json-cases corpus by @samuelcolvin in #266

Try CodSpeed custom runners by @samuelcolvin in #273

Generate the README benchmark table from criterion's results by @samuelcolvin in #274

ci: build wheels for 3.15 by @davidhewitt in #275

ci: use deterministic seed for "big" benchmark by @davidhewitt in #277

Faster aarch64 SIMD string scanning for non-ascii and mask extraction by @samuelcolvin in #270

reduce unsafety & ub by @davidhewitt in #276

Float tests and per-shape benchmarks by @samuelcolvin in #283

Benchmark script summary and validation, LTO for release builds by @samuelcolvin in #282

Disable ASLR for the CodSpeed bench run by @samuelcolvin in #284

Build containers on shared stacks, allocate them exactly once by @samuelcolvin in #269

x86_64 SIMD string scanning and int decoding by @samuelcolvin in #279

use digit run to determine float or integer decode by @davidhewitt in #286

drop Python 3.9, update PGO workflows by @davidhewitt in #288

Add JsonValueScratch, reusable stacks for parsing values by @samuelcolvin in #292

Lock the Python string cache once per parse by @samuelcolvin in #289

Return CPython's singletons for empty and single-character strings by @samuelcolvin in #293

release: 0.17.0 by @samuelcolvin in #294

Full Changelog: v0.16.0...v0.17.0

From the same repository

pydantic/jiter

jitercrates.ioFast Iterable JSON parser

0.16.029 Jun 2026

Drop support for 3.13t target by @Viicos in https://github.com/pydantic/jiter/pull/255

What's Changed

Drop support for 3.13t target by @Viicos in https://github.com/pydantic/jiter/pull/255
update to PyO3 0.29 by @davidhewitt in https://github.com/pydantic/jiter/pull/254
Modernize Emscripten CI by @Viicos in https://github.com/pydantic/jiter/pull/257
Add serde Deserializer implementation by @cetra3 in https://github.com/pydantic/jiter/pull/253

New Contributors

@strawgate made their first contribution in https://github.com/pydantic/jiter/pull/258

Full Changelog: https://github.com/pydantic/jiter/compare/v0.15.0...v0.16.0

Open source →

Additional notes

What's Changed

Drop support for 3.13t target by @Viicos in #255
update to PyO3 0.29 by @davidhewitt in #254
Modernize Emscripten CI by @Viicos in #257
Add serde Deserializer implementation by @cetra3 in #253

New Contributors

@strawgate made their first contribution in #258

Full Changelog: v0.15.0...v0.16.0

Open source →

0.15.019 May 2026

expose known_number_bytes and parser methods for bytes -> number by @davidhewitt in https://github.com/pydantic/jiter/pull/250

What's Changed

expose known_number_bytes and parser methods for bytes -> number by @davidhewitt in https://github.com/pydantic/jiter/pull/250

Full Changelog: https://github.com/pydantic/jiter/compare/v0.14.0...v0.15.0

Open source →

Additional notes

What's Changed

expose known_number_bytes and parser methods for bytes -> number by @davidhewitt in #250

Full Changelog: v0.14.0...v0.15.0

Open source →

0.14.010 Apr 2026

bump PyO3 to 0.28.2 by @rara64 in #234

What's Changed

bump PyO3 to 0.28.2 by @rara64 in #234
ci: add riscv64 target to linux wheel build matrix by @gounthar in #237
Fix Cargo.lock mismatch in generated sdist by @Alex-Izquierdo in #235
Modernize project setup using uv by @Viicos in #240
Avoid stack overflow in PyStringCache by @Viicos in #239
Update to edition 2024, MSRV 1.88 by @Viicos in #243
Update pyodide to 0.28 by @Viicos in #245

New Contributors

@rara64 made their first contribution in #234
@gounthar made their first contribution in #237
@Alex-Izquierdo made their first contribution in #235

Full Changelog: v0.13.0...v0.14.0

Open source →

0.12.09 Nov 2025

chore: pyo3-v0.27.x by @jessekrubin in https://github.com/pydantic/jiter/pull/228

What's Changed

chore: pyo3-v0.27.x by @jessekrubin in https://github.com/pydantic/jiter/pull/228
derive Default for enums by @davidhewitt in https://github.com/pydantic/jiter/pull/229

Full Changelog: https://github.com/pydantic/jiter/compare/v0.11.1...v0.12.0

Open source →

Additional notes

What's Changed

chore: pyo3-v0.27.x by @jessekrubin in #228
derive Default for enums by @davidhewitt in #229

Full Changelog: v0.11.1...v0.12.0

Open source →

0.11.117 Oct 2025

jiter-python: modify pyproject.toml to include license in wheels by @justeph in https://github.com/pydantic/jiter/pull/222

What's Changed

jiter-python: modify pyproject.toml to include license in wheels by @justeph in https://github.com/pydantic/jiter/pull/222
refactor: convert all downcasts to casts by @jessekrubin in https://github.com/pydantic/jiter/pull/221
Upgrade GitHub actions/checkout and actions/setup-python by @cclauss in https://github.com/pydantic/jiter/pull/225
Add GraalPy 3.12 wheels by @msimacek in https://github.com/pydantic/jiter/pull/223
ci: add builds for windows 11 arm by @davidhewitt in https://github.com/pydantic/jiter/pull/210
release: 0.11.1 by @davidhewitt in https://github.com/pydantic/jiter/pull/227

New Contributors

@justeph made their first contribution in https://github.com/pydantic/jiter/pull/222
@cclauss made their first contribution in https://github.com/pydantic/jiter/pull/225

Full Changelog: https://github.com/pydantic/jiter/compare/v0.11.0...v0.11.1

Open source →

Additional notes

What's Changed

jiter-python: modify pyproject.toml to include license in wheels by @justeph in #222
refactor: convert all downcasts to casts by @jessekrubin in #221
Upgrade GitHub actions/checkout and actions/setup-python by @cclauss in #225
Add GraalPy 3.12 wheels by @msimacek in #223
ci: add builds for windows 11 arm by @davidhewitt in #210
release: 0.11.1 by @davidhewitt in #227

New Contributors

@justeph made their first contribution in #222
@cclauss made their first contribution in #225

Full Changelog: v0.11.0...v0.11.1

Open source →

0.11.015 Sept 2025

Impl std::Error for error types by @friendlymatthew in https://github.com/pydantic/jiter/pull/205

What's Changed

Impl std::error::Error for error types by @friendlymatthew in https://github.com/pydantic/jiter/pull/205
Set up criterion for benchmarking by @friendlymatthew in https://github.com/pydantic/jiter/pull/197
Keep strings before incomplete escape sequences in partial mode by @dittos in https://github.com/pydantic/jiter/pull/208
fix lint reported in Rust 1.89 by @davidhewitt in https://github.com/pydantic/jiter/pull/213
Build wheels for GraalPy by @msimacek in https://github.com/pydantic/jiter/pull/212
Trailing bytes partial mode by @PrettyWood in https://github.com/pydantic/jiter/pull/211
Fix linux-x86_64 build matrix by @msimacek in https://github.com/pydantic/jiter/pull/215
allow python_parse to take ref to self by @jessekrubin in https://github.com/pydantic/jiter/pull/214
update PyO3 to 0.26 by @davidhewitt in https://github.com/pydantic/jiter/pull/219
release: 0.11.0 by @davidhewitt in https://github.com/pydantic/jiter/pull/220

New Contributors

@friendlymatthew made their first contribution in https://github.com/pydantic/jiter/pull/205
@dittos made their first contribution in https://github.com/pydantic/jiter/pull/208
@msimacek made their first contribution in https://github.com/pydantic/jiter/pull/212
@PrettyWood made their first contribution in https://github.com/pydantic/jiter/pull/211
@jessekrubin made their first contribution in https://github.com/pydantic/jiter/pull/214

Full Changelog: https://github.com/pydantic/jiter/compare/v0.10.0...v0.11.0

Open source →

Additional notes

What's Changed

Impl std::error::Error for error types by @friendlymatthew in #205
Set up criterion for benchmarking by @friendlymatthew in #197
Keep strings before incomplete escape sequences in partial mode by @dittos in #208
fix lint reported in Rust 1.89 by @davidhewitt in #213
Build wheels for GraalPy by @msimacek in #212
Trailing bytes partial mode by @PrettyWood in #211
Fix linux-x86_64 build matrix by @msimacek in #215
allow python_parse to take ref to self by @jessekrubin in #214
update PyO3 to 0.26 by @davidhewitt in #219
release: 0.11.0 by @davidhewitt in #220

New Contributors

@friendlymatthew made their first contribution in #205
@dittos made their first contribution in #208
@msimacek made their first contribution in #212
@PrettyWood made their first contribution in #211
@jessekrubin made their first contribution in #214

Full Changelog: v0.10.0...v0.11.0

Open source →

0.10.018 May 2025

Bump pyo3 to 0.25, update supported Python versions by @Viicos in https://github.com/pydantic/jiter/pull/198

What's Changed

Bump pyo3 to 0.25, update supported Python versions by @Viicos in https://github.com/pydantic/jiter/pull/198
Fix float_mode default value in from_json() stub definition by @Viicos in https://github.com/pydantic/jiter/pull/199
replace cached_py_string and pystring_fast_new with safe alternatives by @davidhewitt in https://github.com/pydantic/jiter/pull/201

Full Changelog: https://github.com/pydantic/jiter/compare/v0.9.0...v0.10.0

Open source →

Additional notes

What's Changed

Bump pyo3 to 0.25, update supported Python versions by @Viicos in #198
Fix float_mode default value in from_json() stub definition by @Viicos in #199
replace cached_py_string and pystring_fast_new with safe alternatives by @davidhewitt in #201

Full Changelog: v0.9.0...v0.10.0

Open source →

0.9.010 Mar 2025

Update to a current version of lexical-parse-float by @musicinmybrain in https://github.com/pydantic/jiter/pull/182

What's Changed

Update to a current version of lexical-parse-float by @musicinmybrain in https://github.com/pydantic/jiter/pull/182
build wheels for emscripten by @davidhewitt in https://github.com/pydantic/jiter/pull/185
Restore twine check by @Viicos in https://github.com/pydantic/jiter/pull/186
remove SmallVec and LazyIndexMap from json value by @davidhewitt in https://github.com/pydantic/jiter/pull/184
bump pyo3 to 0.24 by @davidhewitt in https://github.com/pydantic/jiter/pull/189

New Contributors

@Viicos made their first contribution in https://github.com/pydantic/jiter/pull/186

Full Changelog: https://github.com/pydantic/jiter/compare/v0.8.2...v0.9.0

Open source →

Additional notes

What's Changed

Update to a current version of lexical-parse-float by @musicinmybrain in #182
build wheels for emscripten by @davidhewitt in #185
Restore twine check by @Viicos in #186
remove SmallVec and LazyIndexMap from json value by @davidhewitt in #184
bump pyo3 to 0.24 by @davidhewitt in #189

New Contributors

@Viicos made their first contribution in #186

Full Changelog: v0.8.2...v0.9.0

Open source →

0.8.026 Nov 2024

Upgrade to PyO3 0.23 by @davidhewitt in https://github.com/pydantic/jiter/pull/137

What's Changed

Upgrade to PyO3 0.23 by @davidhewitt in https://github.com/pydantic/jiter/pull/137
use Bound<'py, PyStr> str equality by @davidhewitt in https://github.com/pydantic/jiter/pull/166
Fix tests without num-bigint feature by @cjwatson in https://github.com/pydantic/jiter/pull/169
support free-threaded Python by @davidhewitt in https://github.com/pydantic/jiter/pull/165
fix linux PGO wheel build by @davidhewitt in https://github.com/pydantic/jiter/pull/170

New Contributors

@cjwatson made their first contribution in https://github.com/pydantic/jiter/pull/169

Full Changelog: https://github.com/pydantic/jiter/compare/v0.7.1...v0.8.0

Open source →

0.7.112 Nov 2024

Fix pyo3 as an optional dependency by @cetra3 in https://github.com/pydantic/jiter/pull/160

What's Changed

Fix pyo3 as an optional dependency by @cetra3 in https://github.com/pydantic/jiter/pull/160
ci: simplify jobs, fix coverage by @davidhewitt in https://github.com/pydantic/jiter/pull/161
update JsonValue allow_partial to use PartialMode by @samuelcolvin in https://github.com/pydantic/jiter/pull/163

New Contributors

@cetra3 made their first contribution in https://github.com/pydantic/jiter/pull/160

Full Changelog: https://github.com/pydantic/jiter/compare/v0.7.0...v0.7.1

Open source →

0.7.031 Oct 2024Deprecated

fix: usage of node12 which is deprecated in CI by @hamirmahal in https://github.com/pydantic/jiter/pull/153

What's Changed

ci: bump jobs to use 3.13, fixes for ubuntu 24.04 by @davidhewitt in https://github.com/pydantic/jiter/pull/154
fix: usage of node12 which is deprecated in CI by @hamirmahal in https://github.com/pydantic/jiter/pull/153
ci: fix run-on-arch action (by updating) by @davidhewitt in https://github.com/pydantic/jiter/pull/155
partial parsing with JsonValue by @samuelcolvin in https://github.com/pydantic/jiter/pull/157

New Contributors

@hamirmahal made their first contribution in https://github.com/pydantic/jiter/pull/153

Full Changelog: https://github.com/pydantic/jiter/compare/v0.6.1...v0.7.0

Open source →

0.6.18 Oct 2024

Fix cargo vendor of jiter crates by @tiran in https://github.com/pydantic/jiter/pull/149

What's Changed

Fix cargo vendor of jiter crates by @tiran in https://github.com/pydantic/jiter/pull/149
release: 0.6.1 by @davidhewitt in https://github.com/pydantic/jiter/pull/150

New Contributors

@tiran made their first contribution in https://github.com/pydantic/jiter/pull/149

Full Changelog: https://github.com/pydantic/jiter/compare/v0.6.0...v0.6.1

Open source →

0.6.07 Oct 2024

improve coverage by @samuelcolvin in https://github.com/pydantic/jiter/pull/117

What's Changed

improve coverage by @samuelcolvin in https://github.com/pydantic/jiter/pull/117
support float_mode='decimal' by @samuelcolvin in https://github.com/pydantic/jiter/pull/116
fix CI by @samuelcolvin in https://github.com/pydantic/jiter/pull/127
correct PyO3 feature usage by @davidhewitt in https://github.com/pydantic/jiter/pull/126
make fuzz checks more lenient by @samuelcolvin in https://github.com/pydantic/jiter/pull/133
iterative algorithm for take_value by @davidhewitt in https://github.com/pydantic/jiter/pull/134
feat: Make num-bigint optional by @fasterthanlime in https://github.com/pydantic/jiter/pull/130
GraalPy support by @steve-s in https://github.com/pydantic/jiter/pull/135
fix codecov coverage by @samuelcolvin in https://github.com/pydantic/jiter/pull/141
Hyperlint accept by @samuelcolvin in https://github.com/pydantic/jiter/pull/142
Fix no-bigint build failures, check those in CI by @fasterthanlime in https://github.com/pydantic/jiter/pull/138
Add examples to jiter-python README by @simonw in https://github.com/pydantic/jiter/pull/143
add builds for 3.13 wheels by @davidhewitt in https://github.com/pydantic/jiter/pull/145
bump version to 0.6.0 by @davidhewitt in https://github.com/pydantic/jiter/pull/147

New Contributors

@fasterthanlime made their first contribution in https://github.com/pydantic/jiter/pull/130
@steve-s made their first contribution in https://github.com/pydantic/jiter/pull/135
@simonw made their first contribution in https://github.com/pydantic/jiter/pull/143

Full Changelog: https://github.com/pydantic/jiter/compare/v0.5.0...v0.6.0

Open source →

0.4.131 May 2024

fix u style unicode strings in python by @samuelcolvin in https://github.com/pydantic/jiter/pull/110

What's Changed

fix u style unicode strings in python by @samuelcolvin in https://github.com/pydantic/jiter/pull/110
convert skip to iterate instead of call recursive functions by @davidhewitt in https://github.com/pydantic/jiter/pull/111

New Contributors

@sydney-runkle made their first contribution in https://github.com/pydantic/jiter/pull/112

Full Changelog: https://github.com/pydantic/jiter/compare/v0.4.0...v0.4.1

Open source →

0.4.022 May 2024

Fix missing license file in published crate by @musicinmybrain in https://github.com/pydantic/jiter/pull/88

What's Changed

Fix missing license file in published crate by @musicinmybrain in https://github.com/pydantic/jiter/pull/88
check duplicate object keys by @samuelcolvin in https://github.com/pydantic/jiter/pull/81
publish python package by @davidhewitt in https://github.com/pydantic/jiter/pull/93
release-python: grant oidc permissions by @davidhewitt in https://github.com/pydantic/jiter/pull/94
attempt to fix test-os by @davidhewitt in https://github.com/pydantic/jiter/pull/95
stricter clippy by @samuelcolvin in https://github.com/pydantic/jiter/pull/97
tweak python package by @samuelcolvin in https://github.com/pydantic/jiter/pull/96
lossless float support by @samuelcolvin in https://github.com/pydantic/jiter/pull/98
try to fix coverage by @samuelcolvin in https://github.com/pydantic/jiter/pull/102
Partial JSON parsing support trailing strings by @samuelcolvin in https://github.com/pydantic/jiter/pull/101
uprev and prepare for release by @samuelcolvin in https://github.com/pydantic/jiter/pull/103
Fix python benchmarks by @samuelcolvin in https://github.com/pydantic/jiter/pull/104
improve coverage in aarch64 SIMD by @samuelcolvin in https://github.com/pydantic/jiter/pull/105
fix build by moving bench deps by @samuelcolvin in https://github.com/pydantic/jiter/pull/106

New Contributors

@musicinmybrain made their first contribution in https://github.com/pydantic/jiter/pull/88

Full Changelog: https://github.com/pydantic/jiter/compare/v0.3.0...v0.4.0

Open source →

0.1.016 May 2024

First release of jiter python package.

Open source →

Additional notes

What's Changed

remove some redundant python reference count ops by @davidhewitt in https://github.com/pydantic/jiter/pull/68
use Cow in JsonValue by @samuelcolvin in https://github.com/pydantic/jiter/pull/63

Full Changelog: https://github.com/pydantic/jiter/compare/v0.0.7...v0.1.0

Open source →