DNS zone file validator that checks BIND records for syntax errors, bad TTLs, missing SOA fields and unterminated names. Runs offline. Free.

a network diagnostic tool.

A web crawler or spider library based on Symfony components - terminal42/escargot

Clinic.js is a suite of tools to help diagnose and pinpoint your Node.js performance issues.

A modern load testing tool, using Go and JavaScript - grafana/k6

fast HTTP/1.1 benchmarking tool written in Node.js - mcollina/autocannon

A command-line benchmarking tool. Contribute to sharkdp/hyperfine development by creating an account on GitHub.

Free desktop SEO crawler - open source alternative to Screaming Frog and similar tools. Crawl websites, analyze links, extract SEO data, and export results without subscription fees. Fully customizable and extensible! - PhialsBasement/LibreCrawl

Weigh the soul of incoming HTTP requests to protect your website!

go-away - Self-hosted abuse detection and rule enforcement against low-effort mass AI scraping and bots.

JavaScript equivalent of XSLT (for JSON/JS objects) - brettz9/jtlt

JSON query and transformation language. Contribute to schibsted/jslt development by creating an account on GitHub.

A very useful and free website analyzer you'll ♥ as a Dev/DevOps, QA engineer, SEO or Security specialist, website owner or consultant. It performs in-depth analyzes of your website, generates an offline or markdown version of the website, provides a detailed HTML audit report and works on all popular platforms - Windows, macOS and Linux (x64 and arm64 too).