The document discusses how SNCF deployed MongoDB replicasets using Docker and MongoDB Ops Manager. It describes combining these tools to create replicasets faster and more reliably. Specific steps included using Ops Manager's API to create groups and policies for backups and alerts. Docker was used to standardize MongoDB deployments across containers and automate operations like starting containers and mounting volumes. The overall goal was to make MongoDB deployments cheaper, faster, and more resilient through automation.