For me it was definitely Emacs and ORG mode. I use this combo to create presentations (pdf + reveal.js), write notes (org-roam style), do project management (ORG mode at its best), collect small code snippets (literal programming in ORG mode), almost everything...
As for a large code base I found ripgrep + rg.el (the interface in Emacs) to be pure gold!
As for a large code base I found ripgrep + rg.el (the interface in Emacs) to be pure gold!