Scheduling

The dependency graph drives execution

Milestones, epics and tickets are nodes; blocks dependencies are edges, at any level (a ticket can block a milestone, a milestone can block a ticket). A ticket is runnable when it is in state ready and every item that blocks it is resolved — done, or cancelled so that abandoned work never stalls its dependents.

Ballet rejects any blocks edge that would create a cycle. Each dependency change also bumps the project’s graph version, so two concurrent additions cannot jointly create a cycle: the second one is re-validated against the updated graph.

Dependencies are limited to items of the same project for now.

The scheduler keeps a ready queue and starts runs up to the configured concurrency limits (globally, per organization, per project). Anything ready runs in parallel; nothing starts before its prerequisites.

The Gantt chart is a forecast

The Gantt chart is the primary human view of a project, computed from the same graph:

• lanes show which work can proceed in parallel;

• sync points are milestones and other join nodes where parallel work must converge;

• the critical path shows which tickets determine the end date;

• durations come from estimates first, then from historical run durations of similar tickets.

Changing the plan (adding a dependency, re-ordering, splitting a ticket) changes the forecast immediately. The Gantt chart never triggers work by itself — the graph and the ready queue do. This keeps execution correct even when estimates are wrong.

Sync points

At a milestone, Ballet can require a human gate before dependent work starts — a natural moment for the human and planner to review direction, update documentation and re-plan.