Related to ranger, nowadays I use lf[0], which is a clone of ranger written in Go. There's also pistol[1] which is a replacement for ranger's rifle file viewer
ranger is fancier (both visually and in terms of configurability), but nnn is significantly faster in my experience. I kept putting off looking into ranger's rifle capabilities and Python scripting, but after having it crash on me a couple times - in a directory with many hundreds of files, to be fair - I tried nnn. The speed and simplicity made me switch over entirely, because it has just the right amount of features that I wanted from ranger. (Well, the one thing I kinda miss is the inline Markdown preview in ranger - shortcut `i` - but it's a minor convenience at best.)
