Semgrep Community Edition

What it is

Semgrep is a static analysis tool for finding bugs, security issues and code patterns across many languages, using rules written in a syntax close to the language itself rather than complex abstract-syntax-tree code. The open source engine and its community rule set have been renamed Semgrep Community Edition (Semgrep CE), consolidating what used to be called Semgrep OSS.

Free versus paid

Semgrep CE is free, needs no account, and installs in a couple of minutes (the docs recommend pipx, with uv and Homebrew as alternatives). As of 2026-09 the engine is licensed under LGPL-2.1, and the official quickstart says the default rule set includes over 1,000 community rules, usable locally or in a CI pipeline at no cost. Semgrep's paid AppSec Platform layers proprietary products such as Semgrep Code, Semgrep Supply Chain and Semgrep Secrets on top, adding cross-file and cross-function analysis, extra proprietary rules and a hosted dashboard; none of that is required to use Semgrep CE.

How to use it

Install the CLI, then run it with a public rule set such as a security audit or OWASP Top Ten pack against your own repository to see how it flags patterns like unsanitised input reaching a dangerous function, hard-coded secrets, or unsafe deserialisation calls. Writing your own rules for a codebase's specific patterns is a natural next step once the built-in rule sets feel familiar.

Who it is for

Developers and security engineers who want fast, mostly-local static analysis without standing up heavier infrastructure. It is commonly wired into pre-commit hooks and CI pipelines so issues are caught before code merges, rather than in a separate, slower audit later.

Prerequisites

Comfort reading code in whatever language you are scanning is the main requirement. No security background is assumed to get started, though understanding common vulnerability classes such as injection and insecure deserialisation helps when triaging what Semgrep finds.

Common questions

Does Semgrep replace manual code review? No, it catches known patterns quickly but misses logic flaws and anything outside its rules; it is a filter that saves review time, not a substitute for it.

Do I need the paid platform to use Semgrep seriously? No, many teams run Semgrep CE alone in CI for years; the paid tiers mainly help larger organisations manage findings across many repositories and add proprietary rules.

How current is the free rule set? The community publishes and updates rules regularly through the Semgrep Registry, and you can also write and share your own.

Does it work offline? Yes, once rules are downloaded, scans run entirely on your own machine with no code sent anywhere, which is one reason security-conscious teams pick it.