Note: in order to receive email reports, you must subscribe to SNS topic fixity in US-West-1. Go to the topic, create subscription, fill in your email and respond to the confirmation email you will get. 
Our serverless fixity program kicks off as an S3 batch job that invokes lambda function fixity check, which in turn calls the Serverless Fixity step machine. Results are left in the cor-devops-binary bucket. When AWS events detect a new report created, lambda function fixity-sns-notification is invoked, which generates a new SNS message in topic fixity checks. Any subscribers to this topic receive an email with a link to the results report.
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