atrium is a macOS desktop app that provides a fully resumable workspace manager with a variety of heterogenous panes including terminals, browsers, tasks, notes, and more.Over the last couple of months, I ve been building an AI development tool that treats CLI AI dev harnesses as first class citizens. With Claude s SDK pricing changes on the horizon, I wanted to avoid getting locked in to paying API rates for something I already had a subscription for.It started after my computer crashed and iTerm didn t restore my sessions, so I set out to solve that problem initially. I liked it and added functionality till it became my daily driver. I ended up with atrium and I m enjoying it so much I thought maybe others would, too.A little about the principles I started following as I built:Organization - everything fits into a hierarchy of workspaces, rooms, panes (agents, terminals, browser, notes, source control, etc), and stacks within a highly customizable mosaic.Persistence - everything, including AI sessions, long-lived processes, rooms, and panes, is saved in real time and restores (and auto-resumes!) in its entirety whether you restart or crash. State is file-based and git backed for extra reliability.Visibility - sidebars surface detailed agent cards, changes, long-lived processes, and activity. In-app and OS notifications keep you on top of everything.Control - atrium ships a comprehensive CLI that allows you and agents to drive anything in atrium: open browser panes, spawn other agents, create tasks or notes, or dream up pretty much anything.It s in early access right now (and I make no guarantees you won t notice) and free to download. All I ask is for feedback :) If you have other solutions to the problems above, I d love to hear em in the comments!Download: https://getatrium.dev Full walkthrough (~22 min): https://www.youtube.com/watch?v=3H7rbn2KFm8