The collection and aggregation of time series data from a variety of heterogenic time series data sources. This may be accomplished through the use of multiple collector modules, each configured to gather time series data from a different time series data source, and translate that time series data from its original format into a common format. An evaluation module applies one or more expressions against the time series data in the common format in order to identify one or more operations to perform, such as alerting, reporting, actuating, and so forth. Accordingly, the principles describe herein allow real world information to be gather and acted upon even when the time series data is gathered from disparate sources. Furthermore, different systems can rely upon the actions being consistent based on access to the same underlying data.