OSS License Deep Dive

Introduction I've always been interested in OSS development. But I was never that interested in licenses. In this article, I'll dig into the actual text of major OSS licenses and uncover the real differences between them. 1. Two Major Camps: Copyleft vs Permissive There are countless OSS licenses, but they fundamentally fall into just two camps. Permissive — "As long as you keep the copyright notice, do whatever you want. Commercial use is fine, no obligation to disclose source code." A generous family of licenses. Copyleft — "Software built with this code must guarantee the same freedoms." A family of licenses with propagation properties. Here, "propagation" means requiring derivative works to adopt the same license (= disclose their source code). Strong Copyleft (GPL/AGPL) extends this obligation to the entire application, while Weak Copyleft (LGPL/MPL) only extends it to modifications of the library portion itself. Whether the source code disclosure obligation propagates to derivati