This has been my goto IDE & text editor for years. A true hidden gem among all the more popular options... p.s. to the person who says "no dark mode", there are themes for Geany you can download. Try Darcula.
Free, easy to use, lightweight, has snippets option, been around a long time. Just wish it had dark mode
This program is simple to use, configurable enough for most of my use cases, and has extended functionality with a nice set of plugins courtesy of the `geany-plugins` package. As someone who finds it difficult to get used to the radically different hotkeys present in Emacs or Vim, this program was incredibly simple to just start being productive with. Is slightly out of date, with version 1.36.1 being offered but 1.37.1 being the latest available.
That is the lightweight IDE I was looking for. Works very well with Python or as external Arduino code editor. Settings are simple and the inverted color mode can be used as a dark theme.