I have managed and designed the Captivate sites since 2014. The platform we chose was WordPress so we could expand the usability of the site for other internal team members to manage.
Organic SEM/SEO: SEO Yoast Premier, SEMrush
Site Speed Test: Tools.pingdom.com, Google Analytics
Lead Gen & Conversion Tracking: Google Ads Conversions, Zapier, Calendly
Retargeting Leads: Facebook Retargetting