Transmission modes
Three ways hits leave your application — queue, sync and batch — switched with one environment variable, and what each one asks of your infrastructure.
Scaling
Where the real ceiling is at high volume, how to measure your own numbers with the load simulator, and how the package composes with Matomo's QueuedTracking plugin.
Reliability
Tracking never blocks a response and never throws into your app. What happens on a failure — retries, throttled alerting, poison batches and the dead-letter queue.