macOS
Homebrewverified · 100%
brew install crf++local Homebrew formula metadata
brew / rank 9291
Install crf++ with Homebrew
Conditional random fields for segmenting/labeling sequential data. Version 0.58 via Homebrew; verified 2026-07-24.
install
Additional install commands
overview
Package summary
Conditional random fields for segmenting/labeling sequential data
Project links
Commands and aliases
- crf_learn
- crf_test
history
Project history and usage
CRF++ is Taku Kudo's open-source Conditional Random Fields toolkit for segmenting and labeling sequential data. Its official page positions it as a generic-purpose CRF implementation for natural-language-processing tasks such as named entity recognition, information extraction, and text chunking.
Project history
The official CRF++ page lists the first release, version 0.1, on 2005-05-28. The release history shows a steady 2005-2007 development period with API work, parallel training, MIRA training, language bindings, L1 regularization, and a license change to LGPL/BSD dual licensing.
Adoption history
CRF++ became a familiar package for NLP users because it combined a command-line learner and tester, a template-based feature system, and bindings for several languages. Later releases focused on compatibility and maintenance, including GCC, libtool, C++11, Windows, and model-loading fixes.
How it is used
Users prepare training and test files plus feature templates, train models with crf_learn, and decode with crf_test. The package is especially associated with sequence-labeling experiments where researchers want a compact C++ CRF implementation available from source or OS packages.
Why package nerds care
For package maintainers, CRF++ is a classic NLP C++ library/CLI: old enough to need build-system care, small enough to package directly, and still recognizable because many downstream tutorials and research pipelines refer to crf_learn and crf_test.
Timeline
- 2005-05-28: CRF++ 0.1 released
- 2006-03-30: Version 0.41 added parallel training
- 2006-11-26: Version 0.45 added 1-best MIRA training
- 2007-02-12: Version 0.46 changed license to LGPL/BSD dual license and added Perl, Ruby, Python, and Java bindings
- 2007-07-07: Version 0.48 added L1-CRF support
- 2013-02-13: CRF++ 0.58 released
Related projects
- CRF++ is related to later CRF sequence-labeling packages such as CRFsuite, which explicitly compares its data-format flexibility with CRF++.
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 bottle metadata was recorded.
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 |
|---|---|---|---|
crf_learn | executable | indexed executable | Discovered from the local executable index. |
crf_test | executable | indexed executable | Discovered from the local executable index. |
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 generated2026-08-03
manager version0.58
manager updated2026-07-24
local dataunknown
upstreamnot available
latest detectednot detected
- okNo freshness warnings were generated.
install metadata
Package metadata
| Package key | brew:crf++ |
|---|---|
| Version | 0.58 |
| Package manager | Homebrew |
| Homepage | https://taku910.github.io/crfpp/ |
| Repository | https://github.com/taku910/crfpp |
| Last updated | 2026-07-24T20:11:30+09:00 |
| Pulse | updated |
| Bottle | not recorded |
| Service | none declared |
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
- cross-ecosystem install command graph
- curated package history
- pkg.so package database
- pkgdb category and tag curation