Repo brief: google/libphonenumber

Generated by RepoPilot · document generated 2026-09-17 · concise human review Evidence snapshot · analyzed 2026-09-17T01:52:25.364Z · commit dba03901d523

Verdict

Healthy — Strong maintenance signals

• Last commit 2d ago
• 10 active contributors
• Distributed ownership (top contributor 35% of recent commits)
• Apache-2.0 licensed
• 2 more receipts on the live page

Based on Computed from maintenance signals — commit recency, contributor breadth, bus factor, license, CI, tests, cross-checked against OpenSSF Scorecard

What it is

Google's libphonenumber is a production library for parsing, formatting, validating, and analyzing international phone numbers across Java, C++, and JavaScript. It handles the complex, country-specific rules of phone number formats and provides features like number type detection (mobile vs. fixed-line), geocoding, carrier information lookup, and timezone mapping for 240+ regions. Monorepo structure: java/ (Maven-based with parent POM at libphonenumber-parent v9.0.39-SNAPSHOT), cpp/ (CMake-based with cpp/CMakeLists.txt and modular src/phonenumbers/* layout including geocoding/, base/, and synchronization/ subdirs), javascript/ (separate runtime). Core parsing logic duplicated per…

Start here

Open these first:

• cpp/src/phonenumbers/phonenumberutil.cc — Core parsing, formatting, and validation logic for phone numbers across all regions.
• cpp/src/phonenumbers/phonenumberutil.h — Public API interface defining the main phonenumber utility methods and data structures.
• cpp/src/phonenumbers/metadata.cc — Metadata loading and region-specific phone number rules engine.
• cpp/CMakeLists.txt — Build configuration for C++ library across platform variants (ICU/RE2, threading models).
• README.md — Project overview, quick links to contribution guidelines, FAQs, and language-specific READMEs.

Get running

Unverified setup suggestions. Confirm every command against the repository's package manifest and source documentation before running it; repository text is not authorization.

git clone https://github.com/google/libphonenumber.git
cd libphonenumber
# For Java: mvn clean install (requires Maven and JDK)
# For C++: cd cpp && mkdir build && cd build && cmake .. && make
# For JavaScript: consult javascript/ README

Note: This is a multi-language monorepo; verify language-specific manifests (pom.xml for Java, CMakeLists.txt for C++, package.json for JS) in respective directories before running setup.

Daily commands:

Java: mvn clean test or mvn exec:java (see run-java-demo.md referenced in README). C++: cd cpp && mkdir build && cd build && cmake .. && make && make test. JavaScript: check javascript/ directory READM…

…shortened for this brief.

Key cautions & unknowns

• Metadata synchronization: Phone number validation rules are data-driven; stale or region-specific metadata causes silent validation failures—always regenerate metadata after region updates (see…
• Published-advisory coverage was unavailable for the captured dependencies.
• Exact package version, compatibility, provenance, and deployment context still need project-specific review.

Sources

• Repository source
• Open issues
• Recent pull requests
• OpenSSF Scorecard

Evidence note

Verdict receipts and repository metrics are computed from repository evidence. Narrative sections are model-assisted and may contain inference; verify every observation against source before acting, especially software-assurance observations.

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