Markers
Markers are little icons used in graphs on AppSignal.com to indicate a change. This can be a code deploy using a "Deploy marker" or a special event with a "Custom marker".
Deploy markers can be used to indicate a change in application version that's deployed, grouping together errors and performance issue per deploy.
Custom markers can be used for anything from scaling operations, to sudden spikes in traffic and infrastructure issues such as when a database was acting up.