How to Set Up Semgrep GitHub Action for Code Scanning

Why run Semgrep as a GitHub Action Semgrep is a fast, open-source static analysis engine that scans code for security vulnerabilities, bugs, and enforced coding patterns. Running it as a GitHub Action means every pull request and push to your main branch is automatically checked against thousands of rules before code reaches production. There is no manual step, no context switching to a separate tool, and no waiting minutes for results. The median Semgrep CI scan finishes in about 10 seconds. The Semgrep GitHub Action fits into two workflows. The first is standalone mode, where you specify rulesets directly in your YAML file and Semgrep runs without any external service. The second is cloud-connected mode, where you link your GitHub repository to Semgrep Cloud (free for up to 10 contributors) and get PR comments, a findings dashboard, AI-powered triage, and policy management from a web interface. Both approaches use the same underlying scan engine. This guide covers every aspect of the