From my perspective, the main difference is the UI footprint and the intended use case. Sklad is intentionally 'passive' and limited to the system tray. It’s not meant to be a full window or a command runner/executor. I built it as a simple warehouse for static data — like passwords, specific IPs, or boilerplate templates — that I need to grab quickly and paste anywhere, whether it’s a terminal, a browser, or a GUI prompt.
I also focused heavily on the recursive folder hierarchy within the native tray menu itself to help with mental mapping, whereas Atuin (and its UI) feels more search-centric and terminal-focused. I think there’s definitely room for both depending on whether you need to execute a command or just grab a piece of secure data.