TJ Holowaychuk

CloudWatch is used for monitoring Lambda functions and alerting on various internal behaviours. Amazon CloudWatch

SES is used for email alert notifications and weekly report summaries. Amazon SES

SNS forms the connective tissue between most of the Lambda functions. Amazon SNS

Postgres is used as the primary data store for users, checks, alerts and so on, as well as some aggregated stats. PostgreSQL

Elasticsearch powers both internal logging and the storage for checks and events. Amazon Elasticsearch Service

All Lambda functions are written in Golang, managed via https://github.com/apex/apex. Go

Lambda powers the monitoring, alerting, and many internal systems such as performing Elasticsearch index garbage collection and maintaining aliases. AWS Lambda