repairjson
repairjson is a Rust-backed Python library that turns common forms of malformed, LLM-style JSON into valid JSON. It is useful at system boundaries where model output is close to JSON but may contain Python literals, missing punctuation, Markdown fences, or a truncated container.
What it repairs
- Single-quoted strings and unquoted object keys
- Python literals such as
True,False, andNone - Missing or trailing commas
- Truncated objects and arrays
- Common malformed number forms
- Raw newlines, tabs, and control characters inside strings
- Leading Markdown fences and conversational preambles before an object or array
The repair engine is byte-oriented and returns compact JSON. loads() performs repair and then delegates deserialization to Python's standard json module.
Installation
python -m pip install repairjson
Quick start
import repairjson
source = "{user: 'alice', active: True, tags: ['x', 'y',],}"
fixed = repairjson.repair(source)
print(fixed)
# {"user":"alice","active":true,"tags":["x","y"]}
value = repairjson.loads(source)
print(value["user"])
# alice
API
repairjson.repair(input: str) -> str
Returns a repaired JSON string. For example:
repairjson.repair("Here is the JSON:\n```json\n{answer: 42}\n```")
# '{"answer":42}'
repairjson.loads(input: str) -> object
Repairs the input and returns the Python value produced by json.loads().
repair_to_string() and repair_json() remain available as compatibility aliases for repair().
Limitations and safety
Repair is heuristic and can be lossy. Ambiguous input may have more than one reasonable interpretation; callers should validate the returned value against an expected schema before using it. The library extracts the first object or array found after a conversational preamble and ignores trailing prose after the parsed value.
This package does not perform schema validation, stream parsing, or security policy enforcement. Apply normal input-size and nesting limits when processing untrusted data. If exact preservation is required, reject malformed input instead of repairing it.
The package is currently an alpha release. See CHANGELOG.md for release history.
Benchmarking
The benchmark harness compares repairjson with the Python json-repair package across generated malformed-input profiles:
uv run --extra benchmark python benchmark.py --dataset all
The benchmark requires Python 3.10 or newer because of its comparison dependency. It checks a sample for semantic equivalence before reporting timings. Results vary with hardware, package versions, and input shape, so the project does not claim a fixed speedup.
Development
Prerequisites: Python 3.8 or newer, Rust stable, and uv.
git clone https://github.com/kyle-mirich/repairjson.git
cd repairjson
uv venv
uv pip install -e ".[dev]"
Run the same checks used by CI:
cargo fmt --check
cargo clippy --all-targets -- -D warnings
cargo test
.venv/bin/python -m pytest -q
Build and inspect release artifacts:
.venv/bin/maturin build --release --sdist -i .venv/bin/python -o dist
.venv/bin/twine check dist/*
Project structure
src/lexer.rs: byte-level input traversal and fence handlingsrc/parser.rs: repair state machine and normalization logicsrc/lib.rs: PyO3 Python APIpython/tests/: end-to-end Python API testsbenchmark.py: generated-corpus benchmark harness.github/workflows/CI.yml: checks, wheels, attestations, and trusted publishingdocs/flows.md: repair and release flows
Contributing
See CONTRIBUTING.md for setup and pull request expectations.
Report security issues privately as described in SECURITY.md.
License
MIT. See LICENSE.
1 maintainer
Metadata
1 maintainer
Release files for repairjson 0.1.3
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| repairjson-0.1.3.tar.gz | 15.8 kB | Details |
Built distributions (wheels)
Total release size: 4.2 MB
Release files / repairjson-0.1.3.tar.gz
| Download URL | repairjson-0.1.3.tar.gz |
|---|---|
| Size | 15.8 kB |
| Tags | Source |
|
SHA-256 checksum How to use checksums |
4f08494563a358c07090309545d342b1ae2ecbe241db4eb04cd2b9a66df5f6c3
|
|
BLAKE2b-256 checksum How to use checksums |
ff784467faa2c137694fe29f6cfebdde73c2a8299d54476bcf8499e79c2da2f3
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-win_arm64.whl
| Download URL | repairjson-0.1.3-cp38-abi3-win_arm64.whl |
|---|---|
| Size | 108.9 kB |
| Tags | CPython 3.8 Windows ARM64 abi3 |
|
SHA-256 checksum How to use checksums |
a51c34fd339df17c53a419f274337d718305461c3a4ee50fdc0e270bfc846bd3
|
|
BLAKE2b-256 checksum How to use checksums |
95d1c7f04c740b95af923e4f9d8630d2ec1a4340c5efab3c5f749128bdbd3230
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-win_amd64.whl
| Download URL | repairjson-0.1.3-cp38-abi3-win_amd64.whl |
|---|---|
| Size | 108.6 kB |
| Tags | CPython 3.8 Windows x86-64 abi3 |
|
SHA-256 checksum How to use checksums |
1ac19c0d3a229001d3bc120a56e2479449827f7f15b42db5483e0297184d2a57
|
|
BLAKE2b-256 checksum How to use checksums |
abc7312bb1d27817ecb352c98b649f76d24008e49313faf17394cbfa26c04ebd
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-win32.whl
| Download URL | repairjson-0.1.3-cp38-abi3-win32.whl |
|---|---|
| Size | 103.2 kB |
| Tags | CPython 3.8 Windows x86-32 abi3 |
|
SHA-256 checksum How to use checksums |
efb0ee54180939a2cbfb80eb9916243e8347e18cd89d47ad7b4c851c1389b38d
|
|
BLAKE2b-256 checksum How to use checksums |
d044f584a796bb106be53a3d592ed4d886b25052af693fa24275a0520a136235
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-musllinux_1_2_x86_64.whl
| Download URL | repairjson-0.1.3-cp38-abi3-musllinux_1_2_x86_64.whl |
|---|---|
| Size | 445.3 kB |
| Tags | CPython 3.8 Linux musl 1.2+ x86-64 abi3 |
|
SHA-256 checksum How to use checksums |
83c98103d774b113dbe087ff6c1e2a0d7da6bfd3930c7dbb4298483437308cc9
|
|
BLAKE2b-256 checksum How to use checksums |
e2f46f92ff1e1e6e5c9dbd024cad7314faf799dd278269c0d5b0b77418d43805
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-musllinux_1_2_i686.whl
| Download URL | repairjson-0.1.3-cp38-abi3-musllinux_1_2_i686.whl |
|---|---|
| Size | 477.2 kB |
| Tags | CPython 3.8 Linux musl 1.2+ x86-32 abi3 |
|
SHA-256 checksum How to use checksums |
39de7c9c3373da0b9bbd90193ffbf794732cd8e6d93793129a9c9fe3d87fde47
|
|
BLAKE2b-256 checksum How to use checksums |
a4bebfb0a77b8d196e3bdb8c8b17b1326a3a6153f805b6e381313cdc362c75b0
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-musllinux_1_2_armv7l.whl
| Download URL | repairjson-0.1.3-cp38-abi3-musllinux_1_2_armv7l.whl |
|---|---|
| Size | 517.8 kB |
| Tags | CPython 3.8 Linux musl 1.2+ ARMv7l abi3 |
|
SHA-256 checksum How to use checksums |
e10a453330e9ed4e6e7cf0d48b0ca17c8e7b768e5c6b76e15226e182ab8a7212
|
|
BLAKE2b-256 checksum How to use checksums |
b2c622d79067b8bc2638366da310bbd77ec6342cd1e90d4166cbcc874080eeb2
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-musllinux_1_2_aarch64.whl
| Download URL | repairjson-0.1.3-cp38-abi3-musllinux_1_2_aarch64.whl |
|---|---|
| Size | 415.2 kB |
| Tags | CPython 3.8 Linux musl 1.2+ ARM64 abi3 |
|
SHA-256 checksum How to use checksums |
e47bf5775ad050cf994683061067f97e9a6a60575c34bfcaa93b05e43c249ec8
|
|
BLAKE2b-256 checksum How to use checksums |
248f992a6ca68824ad40c7cca5275dc8d08b1f2feb53bfc636130552f4a38c38
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl
| Download URL | repairjson-0.1.3-cp38-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl |
|---|---|
| Size | 244.1 kB |
| Tags | CPython 3.8 Linux glibc 2.17+ x86-64 abi3 |
|
SHA-256 checksum How to use checksums |
d5678fcec92ed5fb69440c790a2eee4430fb1af5837ac3d06515c7d7bdb09635
|
|
BLAKE2b-256 checksum How to use checksums |
db02f0a26e1ff7dae691065e5f5136557c96f7524a0ef9799d8d5a8276d8ec82
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-manylinux_2_17_s390x.manylinux2014_s390x.whl
| Download URL | repairjson-0.1.3-cp38-abi3-manylinux_2_17_s390x.manylinux2014_s390x.whl |
|---|---|
| Size | 261.2 kB |
| Tags | CPython 3.8 Linux glibc 2.17+ IBM System/390x abi3 |
|
SHA-256 checksum How to use checksums |
d97bbf59cde7de95609043b50746ad16db97a14a677100dcc3ff336a39cf7c86
|
|
BLAKE2b-256 checksum How to use checksums |
050628a836d7d07a525d28f231473b7df3e4cd97ce3c0f2faa7248e97c879d5d
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-manylinux_2_17_ppc64le.manylinux2014_ppc64le.whl
| Download URL | repairjson-0.1.3-cp38-abi3-manylinux_2_17_ppc64le.manylinux2014_ppc64le.whl |
|---|---|
| Size | 360.5 kB |
| Tags | CPython 3.8 Linux glibc 2.17+ PowerPC 64-le abi3 |
|
SHA-256 checksum How to use checksums |
a4978bd22d8beadf264304a52d1d45efaa9061da0963762036a788ed27171ee6
|
|
BLAKE2b-256 checksum How to use checksums |
6fa0b8364bde29139b7880744416bdde9d3492089e09950ecf9bfc0b1f4e066f
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-manylinux_2_17_armv7l.manylinux2014_armv7l.whl
| Download URL | repairjson-0.1.3-cp38-abi3-manylinux_2_17_armv7l.manylinux2014_armv7l.whl |
|---|---|
| Size | 243.1 kB |
| Tags | CPython 3.8 Linux glibc 2.17+ ARMv7l abi3 |
|
SHA-256 checksum How to use checksums |
863049e69a2635ba16372ebfe355ccbc356af2c24913ccd2ff1d8e09e14a1acc
|
|
BLAKE2b-256 checksum How to use checksums |
9679bf163a5586d99f7953dac988b3ce8b4ad83e1bba6b5bdc650364a165e2e8
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-manylinux_2_17_aarch64.manylinux2014_aarch64.whl
| Download URL | repairjson-0.1.3-cp38-abi3-manylinux_2_17_aarch64.manylinux2014_aarch64.whl |
|---|---|
| Size | 239.2 kB |
| Tags | CPython 3.8 Linux glibc 2.17+ ARM64 abi3 |
|
SHA-256 checksum How to use checksums |
cf0d10e60e02091ffd94f4330b38b27125aa101821a8230dc5d108aa03ca1cfc
|
|
BLAKE2b-256 checksum How to use checksums |
c5cc55b28f6aaf3d8236ddfe93b66f1bb03a7350d41af12c7229617b1e6756c1
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-manylinux_2_5_i686.manylinux1_i686.whl
| Download URL | repairjson-0.1.3-cp38-abi3-manylinux_2_5_i686.manylinux1_i686.whl |
|---|---|
| Size | 257.2 kB |
| Tags | CPython 3.8 Linux glibc 2.5+ x86-32 abi3 |
|
SHA-256 checksum How to use checksums |
77d0d4fa727674f60bb6ad2a7bc96dbf47ee43ab3233b03794f7bfe31a9625da
|
|
BLAKE2b-256 checksum How to use checksums |
f7987ad955486852f974b0e689ccff04a0ed14eaf6e2e9963db79a558f4ce6b4
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-macosx_11_0_arm64.whl
| Download URL | repairjson-0.1.3-cp38-abi3-macosx_11_0_arm64.whl |
|---|---|
| Size | 213.0 kB |
| Tags | CPython 3.8 abi3 macOS 11.0+ ARM64 |
|
SHA-256 checksum How to use checksums |
4894fb239c0ef8d28c561bf17072913838511ee088aef036babb466852efad1b
|
|
BLAKE2b-256 checksum How to use checksums |
278c7b20096ba5692303366ce550d011afec04179d0355e4fd4353ad561e3745
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency logRelease files / repairjson-0.1.3-cp38-abi3-macosx_10_12_x86_64.whl
| Download URL | repairjson-0.1.3-cp38-abi3-macosx_10_12_x86_64.whl |
|---|---|
| Size | 213.0 kB |
| Tags | CPython 3.8 abi3 macOS 10.12+ x86-64 |
|
SHA-256 checksum How to use checksums |
fa442b5bdb97fac5d682963f6bb8076090d87256de7985aaf56929ca6c7595a1
|
|
BLAKE2b-256 checksum How to use checksums |
3c23d7899da0cecea2e04fa28a773d011dd82852d966e465dff0a96732f18811
|
| Upload date | |
|
Uploaded using Trusted Publishing? What is trusted publishing? |
Yes |
| Uploaded via |
twine/6.1.0 CPython/3.13.14
|
Provenance
Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.
PyPI Publish Attestation
PyPI verified that this artifact, at this checksum, originated from the publisher listed below.
Signed by GitHub Actions, verified by PyPI on Jul 23, 2026.
Transparency log
