macOS
Homebrewverified · 100%
brew install grexlocal Homebrew formula metadata
MacPortsverified · 94%
sudo port install grexMacPorts ports tree · textproc/grex/Portfile · source: api.github.com
brew
Install grex with Homebrew, MacPorts, Nix, pacman, scoop, zypper
Command-line tool for generating regular expressions. Version 1.4.6 via Homebrew; verified 2026-06-15.
install
Additional install commands
Linux
Nixverified · 92%
nix profile install nixpkgs#grexnixpkgs package indexes · pkgs/by-name/gr/grex/package.nix · source: api.github.com
Arch Linux pacmanverified · 92%
sudo pacman -S grexArch Linux sync databases · grex · source: geo.mirror.pkgbuild.com
openSUSE zypperverified · 92%
sudo zypper install grexopenSUSE Tumbleweed package metadata · grex · source: download.opensuse.org
Windows
Scoopverified · 92%
scoop install main/grexScoop official bucket manifest trees · bucket/grex.json · source: api.github.com
overview
Package summary
Command-line tool for generating regular expressions
Project links
Commands and aliases
- grex
history
Project history and usage
grex is a Rust command-line tool and library that generates regular expressions from user-provided test cases. It belongs to the developer-tooling tradition around regex synthesis: not replacing regex knowledge, but giving users a correct starting expression that can be inspected and refined.
Project history
The README states that grex began as a Rust port of Devon Govett's JavaScript regexgen project after regexgen development had apparently ceased. Peter M. Stahl's project kept the regex-generation idea but used Rust's strengths for command-line tooling and expanded the feature set beyond the original port.
Official GitHub releases show public versioned releases starting with v0.1.0 on 2019-10-06, followed by v1.0.0 on 2020-02-02. Later releases added and refined library, CLI, Unicode, packaging, and binding surfaces, while the README presents grex as both a command-line executable and a Rust crate with Python bindings.
Adoption history
grex reached package-manager users through the Rust ecosystem first, with crates.io as the upstream registry path, and through binary/package managers such as Homebrew, MacPorts, Scoop, Chocolatey, Huber, Nix, Arch, and openSUSE as reflected by the README and batch package facts. Its packaging surface is broad because it is a single CLI binary but also a reusable library.
How it is used
Users pass examples directly on the command line, from a file, or through a Unix pipeline. By default grex generates a specific expression that matches the supplied test cases; flags can generalize output by converting digits, whitespace, word characters, repeated substrings, anchors, groups, escaping, case sensitivity, verbosity, and colorized display.
The README cautions that generated expressions still need human understanding. That caveat is part of the tool's identity: grex is best used to bootstrap or audit a regex, not to remove the need to understand the target language and engine.
Why package nerds care
grex is package-nerd significant because it packages an algorithmic helper for one of the most common developer annoyances: turning examples into a regular expression. It is also a Rust CLI case study, distributed as source through cargo and as prebuilt binaries or package-manager formulas for users who do not want a Rust toolchain.
Its relationship to regexgen also makes it a small example of ecosystem migration: a JavaScript idea revived as a Rust CLI and library, then exposed through additional language bindings.
Timeline
- 2019: v0.1.0 published in the official GitHub release feed.
- 2020: v1.0.0 published after several 0.x releases.
- 2021: v1.2.0 and v1.3.0 releases continued the 1.x line.
- 2022: v1.4.0 and v1.4.1 releases appeared.
- 2024: v1.4.5 published in the official GitHub release feed.
- 2025: v1.4.6 published with release assets for several operating-system and CPU targets.
Related projects
- regexgen is the JavaScript project that grex began by porting.
- Rust's regex crate is a stated compatibility target for generated expressions.
- grex-js is the related JavaScript/WebAssembly demo and library surface linked from the repository.
- crates.io, PyPI, Homebrew, MacPorts, Scoop, Chocolatey, and Huber are distribution surfaces named by upstream or batch package facts.
Sources
security posture
Risk level: green
narrow executable package without higher-risk signals.
Risk classifier
green risk · low confidence · appliance
Why
- narrow executable package without higher-risk signals
Signals
- metadata:no-higher-risk-signals
Install behavior
- No Homebrew post-install hook is recorded in formula metadata.
- Homebrew bottle metadata is available for 6 platform targets.
- Build metadata lists 1 build dependencies.
Recommended review
Before unattended agent use, check whether the tool reads plaintext credentials, writes remote state, publishes artifacts, or shells out to plugins.
executables
Installed executables
| Command | Kind | Exposure | Note |
|---|---|---|---|
grex | cli | global executable |
freshness
Version and freshness
These signals separate page generation age, package-manager activity, and upstream release comparison. Version lag is warned only when an evidence URL and comparable versions are present.
page generated2026-07-08
manager version1.4.6
manager updated2026-06-15
local dataok
upstreamcurrent
latest detectedv1.4.6
https://github.com/pemistahl/grex
- okNo freshness warnings were generated.
install metadata
Package metadata
| Package key | brew:grex |
|---|---|
| Version | 1.4.6 |
| Package manager | Homebrew |
| Package manager page | https://formulae.brew.sh/formula/grex |
| Homepage | https://pemistahl.github.io/grex-js/ |
| Repository | https://github.com/pemistahl/grex |
| Upstream docs | https://github.com/pemistahl/grex#readme |
| License | Apache-2.0 |
| Source archive | https://github.com/pemistahl/grex/archive/refs/tags/v1.4.6.tar.gz |
| Last updated | 2026-06-15T10:20:17-04:00 |
| Pulse | updated |
| Build dependencies | rust |
| Bottle | available (on arm64_linux, arm64_sequoia, arm64_sonoma, arm64_tahoe, sonoma, x86_64_linux) |
| Homebrew post-install | not defined |
| Service | none declared |
registry facts
Source database details
| Source Database | Homebrew formula API |
|---|---|
| Tap | homebrew/core |
| Full Name | grex |
| Version Scheme | 0 |
| Revision | 0 |
| Bottle Stable Root URL | https://ghcr.io/v2/homebrew/core |
| Deprecated | no |
| Disabled | no |
| Keg Only | no |
| URL Keys |
|
source database matches
Other package-manager records
Matches are pulled from external package-manager indexes and kept separate from local Automic Vault package links.
Nix95%
grex
nix profile install nixpkgs#grex- normalized package name match
- Matched by: Grex
pacman95%
grex 1.4.6-2
A command-line tool for generating regular expressions from user-provided input strings
https://github.com/pemistahl/grex
sudo pacman -S grex- License: Apache-2.0
- Architecture: x86_64
- 2 dependencies
- normalized package name match
- Matched by: Grex
zypper95%
grex 1.4.6-1.2
CLI regex generator
https://github.com/pemistahl/grex
sudo zypper install grex- License: Apache-2.0 AND MPL-2.0 AND MIT AND (Apache-2.0 OR MIT) AND BSL-1.0 AND Apache-2.0 WITH LLVM-exception
- Category: Unspecified
- Architecture: x86_64
- Source Package: grex
- 3 dependencies
- 2 provides
- normalized package name match
- Matched by: Grex
MacPorts95%
grex
sudo port install grex- normalized package name match
- Matched by: Grex
Scoop95%
main/grex
scoop install main/grex- normalized package name match
- Matched by: Grex
source trail
Generated from repository data
This page is generated by av-web from the private package SQLite artifact built by scripts/generate-pkg-sqlite.py.
Combined YAML source
View the package source record on GitHub.
Used sources
- Geiger risk classifier
- Nucleus package database
- av.db category and tag curation
- cross-ecosystem install command graph
- curated package history
- external package-manager database matches
- package relationship graph
- package version freshness
- package-page enrichment