Merlin is a post-exploit Command & Control (C2) tool, also known as a Remote Access Tool (RAT), that communicates using the HTTP/1.1, HTTP/2, and HTTP/3 protocols. HTTP/3 is the combination of HTTP/2 over the Quick UDP Internet Connections (QUIC) protocol. This tool was the result of my work evaluating HTTP/2 in a paper titled Practical Approach to Detecting and Preventing Web Application Attacks over HTTP/2. Merlin is also my first attempts at learning Golang.