Most people wouldn’t know about the tool but the ECO suite of tools for ISPs to manage devices is shit (unless they rewrote it since I last worked on it). Companies paid millions in licensing and the damn thing barely worked. It could take two hours to install despite being bundled as an RPM. Code was also a mess of overrides and black magic techniques that made it near impossible to trace and test. And I just remembered the UI was written in Java and it was source controlled by SVN.