package process_limits

  1. Overview
  2. Docs
Setting time and memory limits for your program


Dune Dependency






This is a small library of utilities used by Semgrep and a few other projects developed at r2c to control the time and memory used by Semgrep.

Published: 27 Jan 2023


Semgrep logo

Code scanning at ludicrous speed.
Find bugs and reachable dependency vulnerabilities in code.
Enforce your code standards on every commit.

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Semgrep is a fast, open-source, static analysis engine for finding bugs, detecting vulnerabilities in third-party dependencies, and enforcing code standards. Get started →.

Semgrep analyzes code locally on your computer or in your build environment: code is never uploaded.

Its rules look like the code you already write; no abstract syntax trees, regex wrestling, or painful DSLs. Here's a quick rule for finding Python print() statements. Run it online in Semgrep’s Playground by clicking the image:

Semgrep rule example for finding Python print() statements

The Semgrep ecosystem includes:

  • Semgrep - The open-source command line tool at the heart of everything (this project).

  • Semgrep Supply Chain - high-signal dependency scanner that detects reachable vulnerabilities in third-party libraries and functions across the SDLC.

  • Semgrep App - Deploy, manage, and monitor Semgrep and Semgrep Supply Chain at scale with free and paid tiers. Integrates with CI providers such as GitHub, GitLab, CircleCI, and more.


  • Semgrep Playground - An online interactive tool for writing and sharing rules.

  • Semgrep Registry - 2,000+ community-driven rules covering security, correctness, and dependency vulnerabilities.

Join hundreds of thousands of other developers and security engineers already using Semgrep at companies like GitLab, Dropbox, Slack, Figma, Shopify, HashiCorp, Snowflake, and Trail of Bits.

Semgrep is developed and commercially supported by r2c, a software security company.

Language support

General availability

C# · Go · Java · JavaScript · JSX · JSON · PHP · Python · Ruby · Scala · TypeScript · TSX

Beta & experimental

See supported languages for the complete list.

Getting started

To install Semgrep use Homebrew or pip, or run without installation via Docker:

# For macOS
$ brew install semgrep

# For Ubuntu/WSL/Linux/macOS
$ python3 -m pip install semgrep

# To try Semgrep without installation run via Docker
$ docker run --rm -v "${PWD}:/src" returntocorp/semgrep semgrep

Once installed, Semgrep can run with single rules or entire rulesets. Visit Docs > Running rules to learn more or try the following:

# Check for Python == where the left and right hand sides are the same (often a bug)
$ semgrep -e '$X == $X' --lang=py path/to/src

# Fetch rules automatically by setting the `--config auto` flag.
# This will fetch rules relevant to your project from Semgrep Registry.
# Your source code is not uploaded.
$ semgrep --config auto

To run Semgrep Supply Chain, contact the Semgrep team. Visit the full documentation to learn more.

Rule examples

Visit Docs > Rule examples for use cases and ideas.

Use case Semgrep rule
Ban dangerous APIs Prevent use of exec
Search routes and authentication Extract Spring routes
Enforce the use secure defaults Securely set Flask cookies
Tainted data flowing into sinks ExpressJS dataflow into
Enforce project best-practices Use assertEqual for == checks, Always check subprocess calls
Codify project-specific knowledge Verify transactions before making them
Audit security hotspots Finding XSS in Apache Airflow, Hardcoded credentials
Audit configuration files Find S3 ARN uses
Migrate from deprecated APIs DES is deprecated, Deprecated Flask APIs, Deprecated Bokeh APIs
Apply automatic fixes Use listenAndServeTLS


Visit Docs > Extensions to learn about using Semgrep in your editor or pre-commit. When integrated into CI and configured to scan pull requests, Semgrep will only report issues introduced by that pull request; this lets you start using Semgrep without fixing or ignoring pre-existing issues!


Browse the full Semgrep documentation on the website. If you’re new to Semgrep, check out Docs > Getting started or the interactive tutorial.


Using remote configuration from the Registry (like --config=p/ci) reports pseudonymous rule metrics to

Using configs from local files (like --config=xyz.yml) does not enable metrics.

To disable Registry rule metrics, use --metrics=off.

The Semgrep privacy policy describes the principles that guide data-collection decisions and the breakdown of the data that are and are not collected when the metrics are enabled.



To upgrade, run the command below associated with how you installed Semgrep:

# Using Homebrew
$ brew upgrade semgrep

# Using pip
$ python3 -m pip install --upgrade semgrep

# Using Docker
$ docker pull returntocorp/semgrep:latest

Dependencies (3)

  1. commons >= "1.5.5"
  2. dune >= "3.2.0"
  3. ocaml >= "4.12.0"

Dev Dependencies


Used by (1)

  1. profiling




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