The system everything else runs on
The platform I run the whole portfolio from: tasks, projects, clients, and the fleet of coding agents working on them in parallel.
When several AI agents work on one repository at once, they start overwriting each other's work, duplicating tasks and losing context between sessions. Without shared memory, parallel work becomes a delay rather than a speed-up.
Playground gives agents one shared task list, blueprints holding the architecture, and a work board with file locks. An agent checks what the others are doing before it starts, locks its files, and releases them after committing. I see the same thing through the web interface.
Tasks, epics, projects and clients in one place, for me and for the agents working on them.
Living architecture documentation that agents read before the work and update after it.
File locks and a coordination channel that keep parallel sessions off each other's toes.
I don't sell Playground as a product. It's the reason I can run this many projects at once.