---
id: regress
version: "2025.10.1"
license: unclear
license_treatment: permissive
maintenance: aging
---

# regress — Python bindings to Rust's regress ECMA regular expressions library

License: permissive · Maintenance: aging · Downloads: 4.1M/mo

## What it is and what it does

Regress is a Python wrapper around the Rust regress crate that implements ECMA-compliant regular expressions. Unlike Python's built-in re module, which follows Perl-style regex semantics, regress exposes JavaScript/ECMAScript regex behavior through a simple Regex class with methods like find() for pattern matching.

The package is distributed as precompiled wheels for Python 3.10–3.14 on multiple platforms (Linux, macOS, Windows, and various CPU architectures), eliminating the need to compile Rust code during installation on supported systems. It has no runtime dependencies beyond the Python standard library, making it lightweight to add to an existing project. The package is in Beta status and has not been updated recently, suggesting a stable but not actively developed codebase.

Use it for:

- Match patterns using ECMAScript regex syntax when porting JavaScript code to Python or maintaining cross-platform regex consistency.
- Validate input strings with ECMA-compliant patterns in web applications or data processing pipelines.
- Perform regex operations where JavaScript regex semantics are required rather than Python's default Perl-style behavior.
- Extract substrings or check pattern presence using the find() method in text processing workflows.

## Worth the install?

AI-flagged interpretation of the facts above — verify before relying.

Provides Python bindings to the Rust regress crate for ECMA-compliant regular expression matching, offering an alternative regex engine to Python's built-in re module.

Yes, if you need ECMA-compliant regex semantics and are on Python 3.10 or later. The permissive MIT license, zero runtime dependencies, and precompiled wheels make it low-friction to adopt. However, the aging maintenance status and Beta classification mean you should verify that ECMA regex behavior is actually required for your use case—Python's built-in re module is more actively maintained and sufficient for most applications.

## Install

pip install regress
uv add regress
poetry add regress

## Installing regress

Before you install: Medium install friction due to compiled wheels; prebuilt binaries available for Python 3.10–3.14 across Linux, macOS, and Windows architectures. Package is aging with Beta status, so expect slower maintenance cadence.

License in practice: MIT license (permissive); no restrictions on commercial or private use, modification, or redistribution as long as the license and copyright notice are included.

Quickstart:

pip install regress

from regress import Regex
regex = Regex(r"\d{4}")
result = regex.find("2020-20-05")

Requires Python 3.10 or later; compiled wheels are available for common platforms but may require a build environment on unsupported architectures.

Verify before relying:

- Performance characteristics compared to Python's built-in re module or other regex libraries in typical use cases.
- Specific ECMA regex feature coverage and any known limitations versus full ECMAScript specification.
- Activity level and responsiveness of maintainers given the aging status and no recent commits visible.

## Package facts

- License: not declared (permissive)
- Python support: supports_current
- Install friction: medium
- Maintenance: aging
- Downloads: 4.1M/month (top 5,000 on PyPI)
- Known vulnerabilities: none known

## Tags

ecma regex python, rust regex bindings, javascript regex engine, regex alternative library, ecmascript regular expressions, regress python bindings, rust-backed regex, regex-engine, rust-bindings, ecmascript

[View on SkillFed](https://skillfed.io/packages/regress) · [View on PyPI](https://pypi.org/project/regress/)