BBEdit

my favourite text-editor for smaller scripts - specially the very powerful and intuitive search and replace function is great in this app. additionally you can easily run and check your scripts directly inside the app

A powerful, versatile (and venerable!) text editor for macOS that still manages to be fast and stay out of your way so you can just write. It's light enough that I use it for jotting down notes instead of opening TextEdit, and it's capable enough that I can open multi-megabyte files, filter duplicates, sort, do regex-based search and replace, run external commands, and more. On occasion I've opened giant CSVs to run a search-and replace, sort, and then filter in here, because I can finish the whole thing faster than I can get Excel or Numbers to even load the file.

There's a free mode that replaces TextWrangler (which used to be the free-equivalent), but I've been quite happy to pay for the full version. If you're coming from Windows and miss Notepad++, this is the app to use.

BBEdit is insanely great. I have been using text editors for almost 25 years now, starting with C64, Atari ST, then MacOS, Windows and back to OS X. BBEdit is easily the most-customizable, reliable and feature-rich text editor I have worked with. I use it for HTML, CSS, e-mail and about everything else that doesn't require visual formatting. GREP, syntax coloring, project management ... There's a lot to discover. It's not cheap, but well worth the money if words (or code) are your daily business.