Datadog is a popular metric collecting service used by Peloton Cycle to collect server and application metrics. The company uses Datadog's integrations with various software, including NGINX, to monitor system health and business indicators. However, they found that the out-of-the-box integration with Redis was not accurate enough for their needs, so they developed a custom solution using DogStatsD to monitor riders with structured data. Additionally, Peloton Cycle uses Datadog's AgentCheck framework to implement custom checks for replica or standby monitoring of their Redis and PostgreSQL databases. They found that Datadog is developer-friendly, easy to customize, and suitable for conveying system and business metrics to a company-wide audience.