Snyk - Snyk helps you use open source and stay secure. Continuously find and fix vulnerabilities for npm, Maven, NuGet, RubyGems, PyPI and much more.
Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.
Zscaler Web Security - Zscaler offers cloud-based web security solutions.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
McAfee Secure - McAfee SECURE is a security certification for websites.
Better Uptime - We call you when your website goes down