Install weggli with Homebrew, apk, Nix, zypper

Project links

• Homepage

Commands and aliases

• weggli

Project history

The current GitHub repository was created in September 2021, and crates.io metadata shows package publication beginning in October 2021. The README states that weggli is inspired by Semgrep, Coccinelle, joern, and CodeQL, but intentionally makes different tradeoffs for C/C++ review.

Those tradeoffs define the project: first-class support for modern C++ constructs, minimal setup without requiring a successful build, interactive performance, and greedy matching that finds useful variants even at the cost of false positives. The implementation is built on tree-sitter C and C++ grammars, with queries translated into tree-sitter query machinery plus weggli-specific behavior.

Adoption history

weggli's adoption is strongest in vulnerability research and manual code-review circles rather than general developer search. A 2024 HN Security article described converting C/C++ vulnerability patterns from Semgrep into weggli queries and using the tool to identify hotspots such as buffer overflows, integer issues, format strings, memory-management mistakes, and command-injection patterns.

By July 2026, the repository had about 2.5 thousand GitHub stars, which is sizable for a specialized security CLI. Its package-manager niche is clear: it gives reviewers a fast semantic grep for C and C++ without requiring a full CodeQL database, compiler build, or heavyweight SAST workflow.

How it is used

A typical invocation is `weggli <PATTERN> <PATH>`, where the pattern is written in a C/C++-like language with metavariables and wildcards. For example, patterns can look for a stack buffer followed by a `memcpy` call, suspicious arithmetic before allocation, or API-specific call sequences.

In practice, users run weggli interactively while reading source: write a pattern, inspect matches, refine the query, and then manually audit nearby code. It is especially useful for variant analysis after one bug is found and for quickly mapping attack-surface idioms in unfamiliar C/C++ projects.

Why package nerds care

weggli is package-nerd significant because it is the small, installable middle ground between `grep` and heavyweight static-analysis platforms. It makes AST-aware C/C++ searching feel like a fast CLI habit rather than an infrastructure project.

Timeline

• 2021-09: GitHub repository created.
• 2021-10: crates.io package created and early 0.2.x releases began.
• 2022-05: v0.2.4 release published.
• 2024-01: HN Security published a practitioner pattern collection and workflow article for C/C++ vulnerability research.

Related projects

• The README names Semgrep, Coccinelle, joern, and CodeQL as inspirations. In use, weggli is closest to a semantic grep for C/C++ reviewers, while those related tools cover broader rule management, program analysis, source transformation, or database-backed code queries.

Sources

• https://api.github.com/repos/weggli-rs/weggli
• https://api.github.com/repos/weggli-rs/weggli/releases?per_page=5
• https://crates.io/api/v1/crates/weggli
• https://github.com/weggli-rs/weggli
• https://hnsecurity.it/blog/a-collection-of-weggli-patterns-for-c-cpp-vulnerability-research/