Cloudflare is a web-infrastructure and website-security company, providing content-delivery-network services, DDoS mitigation, Internet security, and distributed domain-name-server services.
Facebook pixel is an analytics tool that allows you to measure the effectiveness of your advertising.
hCaptcha is an anti-bot solution that protects user privacy and rewards websites.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.
Sentry is an open-source platform for workflow productivity, aggregating errors from across the stack in real time.
Stripe offers online payment processing for internet businesses as well as fraud prevention, invoicing and subscription management.