srsly
Modern high-performance serialization utilities for Python
Decision gist · record as of 2026-08-14
Yes. srsly is actively maintained, has no known vulnerabilities, and offers genuine value if you need multiple serialization formats in one place. The MIT license is permissive. Install friction is moderate due to compiled components, but pre-built wheels are widely available. Worth installing if you're building on spaCy, Prodigy, or similar data-heavy tools, or if you want to consolidate serialization dependencies.AI-flagged interpretation of the facts on this page — verify before relying
Before you install
- Medium install friction due to compiled components (Cython), but pre-built wheels are available for common platforms and Python versions.
- Actively maintained with recent releases; no known vulnerabilities.
License · maintenance · safety
MIT (permissive) — MIT license permits commercial and private use with minimal restrictions; you may use, modify, and distribute srsly freely provided you include the license notice.
last release 2026-03-23 (144 days) · last repo commit 2026-03-27 · 484 stars
0 known vulnerabilities (OSV.dev, 2026-08-14) · 21,618,409 downloads/mo, #994 on PyPI
Alternatives
Verify before relying
import srsly
data = {"foo": "bar", "baz": 123}
json_string = srsly.json_dumps(data)
obj = srsly.json_loads(json_string)
srsly.write_json("/path/to/file.json", data)
loaded = srsly.read_json("/path/to/file.json")- Whether the included forks of ujson, msgpack, msgpack-numpy, cloudpickle, and ruamel.yaml are kept in sync with upstream security patches.
- Performance characteristics compared to using the underlying libraries directly.
What it is and what it does
srsly is a serialization utility package that bundles JSON, JSONL, MessagePack, Pickle, and YAML support into a single binary wheel. It wraps multiple well-known serialization libraries (ujson, msgpack, cloudpickle, ruamel.yaml) as internal forks, eliminating the need to manage them as separate dependencies while providing a consistent high-level API across all formats.
The package solves the problem of serialization inconsistencies across Python versions and platforms by centralizing encoding, locale, and file-handling logic. It's typically used in data processing pipelines, machine learning workflows, and applications that need to persist or transmit structured data reliably. The single-wheel distribution model reduces installation complexity and maintenance overhead compared to managing multiple small dependencies.
Use it for
- Serialize and deserialize structured data in machine learning pipelines where multiple formats (JSON, MessagePack, Pickle) are needed.
- Write and read gzip-compressed JSON or JSONL files for efficient storage of large datasets.
- Provide a consistent serialization interface across spaCy, Prodigy, and other NLP/data tools that need platform-independent data handling.
- Handle cross-Python-version compatibility issues by abstracting away encoding and locale quirks in serialization.
- Replace multiple small serialization dependencies with a single pre-compiled wheel to speed up installation.
Worth the install?
AI-flagged interpretation of the facts on this page. Verify before relying on it.
Yes.
srsly is actively maintained, has no known vulnerabilities, and offers genuine value if you need multiple serialization formats in one place. The MIT license is permissive. Install friction is moderate due to compiled components, but pre-built wheels are widely available. Worth installing if you're building on spaCy, Prodigy, or similar data-heavy tools, or if you want to consolidate serialization dependencies.
Install
srsly on PyPI
Before you install
Medium install friction due to compiled components (Cython), but pre-built wheels are available for common platforms and Python versions. Actively maintained with recent releases; no known vulnerabilities.
License in practice
MIT license permits commercial and private use with minimal restrictions; you may use, modify, and distribute srsly freely provided you include the license notice.
Quickstart
import srsly
data = {"foo": "bar", "baz": 123}
json_string = srsly.json_dumps(data)
obj = srsly.json_loads(json_string)
srsly.write_json("/path/to/file.json", data)
loaded = srsly.read_json("/path/to/file.json")Verify before relying
- Whether the included forks of ujson, msgpack, msgpack-numpy, cloudpickle, and ruamel.yaml are kept in sync with upstream security patches.
- Performance characteristics compared to using the underlying libraries directly.
Package facts
| License | MIT permissive |
| Python support | Supports the current Python release <3.15,>=3.9 |
| Install friction | Medium. Platform-specific wheel |
| Runtime dependencies | 1 packagecatalogue |
| Maintenance | Actively maintained 144 days since the last release |
| Last repo commit | |
| First released | |
| Downloads | 21,618,409 / month, #994 on PyPI 30-day window, as of 2026-08-14 |
| Known vulnerabilities | None known OSV.dev, checked 2026-08-14 |
| Classifiers | Development Status :: 5 - Production/StableEnvironment :: ConsoleIntended Audience :: DevelopersIntended Audience :: Science/ResearchLicense :: OSI Approved :: MIT LicenseOperating System :: MacOS :: MacOS XOperating System :: Microsoft :: WindowsOperating System :: POSIX :: LinuxProgramming Language :: CythonProgramming Language :: Python :: 3Programming Language :: Python :: 3.10Programming Language :: Python :: 3.11Programming Language :: Python :: 3.12Programming Language :: Python :: 3.13Programming Language :: Python :: 3.9Topic :: Scientific/Engineering |
Evidence: srsly-2.5.3-cp310-cp310-macosx_10_9_x86_64.whl; srsly-2.5.3-cp310-cp310-macosx_11_0_arm64.whl; srsly-2.5.3-cp310-cp310-manylinux2014_aarch64.manylinux_2_17_aarch64.whl; srsly-2.5.3-cp310-cp310-manylinux2014_x86_64.manylinux_2_17_x86_64.whl; srsly-2.5.3-cp310-cp310-musllinux_1_2_aarch64.whl; srsly-2.5.3-cp310-cp310-musllinux_1_2_x86_64.whl; srsly-2.5.3-cp310-cp310-win_amd64.whl; srsly-2.5.3-cp310-cp310-win_arm64.whl; srsly-2.5.3-cp311-cp311-macosx_10_9_x86_64.whl; srsly-2.5.3-cp311-cp311-macosx_11_0_arm64.whl; srsly-2.5.3-cp311-cp311-manylinux2014_aarch64.manylinux_2_17_aarch64.whl; srsly-2.5.3-cp311-cp311-manylinux2014_x86_64.manylinux_2_17_x86_64.whl; srsly-2.5.3-cp311-cp311-musllinux_1_2_aarch64.whl; srsly-2.5.3-cp311-cp311-musllinux_1_2_x86_64.whl; srsly-2.5.3-cp311-cp311-win_amd64.whl; srsly-2.5.3-cp311-cp311-win_arm64.whl; srsly-2.5.3-cp312-cp312-macosx_10_13_x86_64.whl; srsly-2.5.3-cp312-cp312-macosx_11_0_arm64.whl; srsly-2.5.3-cp312-cp312-manylinux2014_aarch64.manylinux_2_17_aarch64.whl; srsly-2.5.3-cp312-cp312-manylinux2014_x86_64.manylinux_2_17_x86_64.whl
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