Java ME (Micro Edition, also referred to as J2ME) is a platform for running Java applications on small resource constrained devices, such as feature phones from before the iPhone era. It is largely considered a dead platform with the advent of smartphones, and modern feature phones such as KaiOS use web technologies instead for their apps. However it is likely that you or someone you know have one of these old phones lying around, and you may be interested in how you can make Java apps that will run on it. This post goes through how to build a simple Java ME app solely with modern tooling in a modern environment, without needing anything from the old Sun Java ME SDKs.