There are many alternatives to GNU nano for Mac if you are looking for a replacement. The best Mac alternative is Visual Studio Code, which is free. If that doesn't suit you, our users have ranked more than 100 alternatives to GNU nano and loads of them are available for Mac so hopefully you can find a suitable replacement. Other interesting Mac alternatives to GNU nano are Atom (Free, Open Source), Sublime Text (Free Personal), Vim (Free, Open Source) and VSCodium (Free, Open Source).
Bluefish is a powerful editor targeted towards programmers and webdesigners, with many options to write websites, scripts and programming code. Bluefish supports many programming and markup languages, and it focuses on editing dynamic and interactive websites.
CudaText is a cross-platform text editor, written in Lazarus. It starts quite fast (0.5 sec with ~30 plugins on CPU Intel Core i3 3Hz). It is extensible by Python add-ons (plugins, linters, code tree parsers, external tools).
Left is a distractionless writing tool with auto-complete, a synonyms dictionary, writing statistics, markup-based navigation and a speed-reader. The application is free and Open Source, its original purpose was to help Rekka with the writing of the upcoming novel Wiktopher.