Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Fiddler - Fiddler is a debugging program for websites.
Attendize Event Ticketing - Attendize is a free & open-source ticket selling and event management platform
Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
pretix - pretix helps you to sell tickets for your event in an easy way. It supports multi-lingual events and provides a wide range of features
HTTP Toolkit - Beautiful, cross-platform & open-source tools to debug, test & build with HTTP(S). One-click setup for browsers, servers, Android, CLI tools, scripts and more.