A task like "Prepare the team offsite" is rarely one task. Most of the time it's five smaller ones, and until now you had to keep those pieces in your head or type them out as plain lines in a note. Now you can break a task apart in the same place you were already writing it.
Sub-tasks live inside the private note you already have. Open any task, type / and choose Checklist, or just type [] to start one. Each item becomes a sub-task, and progress shows up right on the block, so you know where a task stands without opening it.
We deliberately designed sub-tasks to go only one level deep. We could have built a nested structure, and plenty of tools do. We didn't, because Arch Calendar is a tool for holding your tasks, notes, and schedule in one simple view. A deep hierarchy ends up being something you maintain instead of something you work on. One level is enough to break a task down. Go deeper than that and we think you're organizing your work rather than doing it.














