OpenGrep vs Pysa

OpenGrep is a free, open-source static analysis engine for finding security issues and searching patterns in source code. It runs on Linux, macOS, and Windows, with self-hosted deployment. The project supports more than 30 languages, including Python, Java, JavaScript, Go, Rust, PHP, and Visual Basic, and existing Semgrep rules and rulesets work without changes. Its intrafile taint analysis tracks constructor and field assignments, flow between methods, higher-order functions across 12 languages, and collection operations such as map, filter, and reduce. OpenGrep produces JSON and SARIF output and documents a CI subcommand for workflow use. The project distributes self-contained binaries and says releases are signed with Cosign. OpenGrep is a Semgrep fork under the LGPL 2.1 license. The security policy requests vulnerability reports by email and lists only the latest version as supported.

Pysa is a free, open-source Python static analysis tool that uses taint analysis to identify potential security issues. It follows data from configured sources toward dangerous sinks, such as user-controlled request data reaching an eval call. Users configure sources, sinks, features and rules in taint.config, and annotate code with .pysa model files; built-in and common Python libraries have prewritten models and rules. Sanitizer models describe data that should lose taint, including function parameters and return values. Pysa analyzes the target repository and directories in the configured search_path, but not dependency source outside that scope. When it cannot access a function’s source, it assumes the return value retains taint, which can lead to false positives. Analysis may freeze on similarly sized projects if the machine lacks enough memory. The quickstart installs it with pip install pyre-check in a Python virtual environment. Pyre supports the Language Server Protocol, and a VSCode extension connects to a running server. SAPP can ingest results for viewing and filtering in a local web UI; a GitHub Action can run Pysa in CI and show findings in GitHub’s Security code scanning UI. Pysa requires Python 3.9 or later and relies on type information from Pyrefly. The project says it can analyze codebases with millions of lines. Its repository is MIT-licensed; the Pyre repository was archived on June 26, 2026, and says Pysa moved to its own repository.