Immediate cause: A transient database connectivity issue caused some data to be inaccessible to the sync process responsible for distributing it to edge nodes, causing a new constraint check within siteverify to fail for some users as this code change deployed across our network and edge services restarted without access to the required data.
Root cause: The root cause of this issue was an unintentional dependency on database access added during a recent code change to more stringently enforce some per-user constraints on the siteverify call, which has now been addressed.
Resolution: The database connectivity issue was resolved, and the constraint check was improved to handle the no-data-available case correctly.
Ongoing work: All parts of our system are designed to continue functioning fully even during internal issues like database connectivity failures. We are implementing an additional set of CI/CD safeguards to more aggressively verify that this behavioral contract is maintained for all code changes.