Add concurrent branches and merge operators #19

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opened 2026-09-16 21:54:39 +02:00 by morten-olsen · 0 comments

morten-olsen commented

2026-09-16 21:54:39 +02:00

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Deferred while adding audio playback, where a "play sound, meanwhile carry on" shape would have wanted it.

Why it is not a small change

The scheduler is deterministic and topological: it executes one node at a time over a compiled plan. Parallel lanes need
more than a fan-out node.

per-lane durable checkpoints, since any lane may suspend independently while others continue;
merge semantics, which ENGINE.md still lists as future work, including how empty batches from an unselected branch reach a merge;
cancellation and failure policy across lanes: whether one lane failing cancels its siblings, and what the run outcome is;
run inspection and captured-run debugging, which currently assume a single ordered node sequence.

What covers the gap today

Fire-and-forget plus wait for duration covers the "start something, continue, act later" shape. audio.play with
waiting enabled suspends on a correlated completion event, so the stop notification releases the run without a parallel
lane. This is enough for alert-style automations but not for genuinely independent work.

Deferred while adding audio playback, where a "play sound, meanwhile carry on" shape would have wanted it. ## Why it is not a small change The scheduler is deterministic and topological: it executes one node at a time over a compiled plan. Parallel lanes need more than a fan-out node. - per-lane durable checkpoints, since any lane may suspend independently while others continue; - merge semantics, which ENGINE.md still lists as future work, including how empty batches from an unselected branch reach a merge; - cancellation and failure policy across lanes: whether one lane failing cancels its siblings, and what the run outcome is; - run inspection and captured-run debugging, which currently assume a single ordered node sequence. ## What covers the gap today Fire-and-forget plus `wait for duration` covers the "start something, continue, act later" shape. `audio.play` with waiting enabled suspends on a correlated completion event, so the stop notification releases the run without a parallel lane. This is enough for alert-style automations but not for genuinely independent work.

morten-olsen referenced this issue from a commit

2026-09-16 21:55:13 +02:00

docs(engine): record correlated continuations, file references and audio

morten-olsen added the

feature

label

2026-09-17 08:19:57 +02:00