Every library is code I have to maintain without even knowing what's inside. I only use libraries for something I absolutely can't write myself, like PGP. I a

Every library is code I have to maintain without even knowing what's inside. I only use libraries for something I absolutely can't write myself, like PGP. I also avoid languages and technologies which introduce breaking changes. e.g. Python will never be a top-level language in my project, only an optional add-on for scripting, with failure checks.