Detailed flows

For engineers building the integration. Each flow names every call and what your code does when something goes wrong. The contract for each call is in the API reference; the events are in Events.

Finished series

Forming series: the edge travels with you

Patternode keeps nothing between calls. The series' state is its edge, which lives in your segment store and is sent with each new bar.

Rules your code keeps:

Situation	Answer	Do
A retried request	The same answer, whichever region gives it	Store it as usual
A bar before the edge's last close	409 out_of_order	Drop it, or rebuild the window as a finished series
An edge from another series or profile version	409 edge_mismatch	Read this series' edge from your store
A changed or truncated edge	400 edge_invalid	Store edges as opaque strings, exactly as received
Two writers on one series	Both answers are valid	Keep the first write: a version check in your store
Your workload restarted		Read the edge from your store and carry on
You lost a series' edge		Send the series again as a finished series with return_edge: true

The life of a forming series, on your side:

Backfill, with a webhook

Rotating credentials without downtime

Next: Decisions you make.