Techniques and mechanisms described herein provide for verification of data across cloud-based and on-premises data storage systems. According to various embodiments, a backup client implemented on a first compute node can store a data file in a backup data repository. A data guardianship can store first data file state information describing the data file in a key-value store accessible via the internet. A data verification instance can analyze the backup data repository to verify that the data file is stored intact in the backup data repository.