MULTI-SERVICE STORAGE LAYER FOR STORING APPLICATION-CRITICAL DATA

Techniques are described for providing a multi-service storage layer in a cloud provider network for applications and workloads that are highly sensitive to outages affecting "mission critical" data or other resources. A multi-service storage layer is designed to provide additional resiliency against various types of correlated failures among existing geographic regions by enabling the storage of data using a plurality of separate storage services and storage resource types and across a plurality of regions of the cloud-provider network. A multi-service storage layer provides an application programming interface (API) with actions for storing, retrieving, and querying data stored in a highly available storage resource across a selection of underlying storage services. The ability to store critical data and other resources using a multi-service storage layer provides additional resiliency while also providing a single interface that applications can use to interact with the data stored across any number of underlying storage services.