VTL E&E is an interpreterengine and an editor for theValidation and Transformation Language, adeclarative,metadata-driven language developed in the context of theSDMX standard with the goal of standardizing data validations and transformations.

The E&E core libraries are developed in Java. The goal of this tool is to help users learn VTL and work with it in the most comfortable and usual way. For this reason, the preferred engine front-end is the RVTL R package (though the java engine can be used independently from R as well). The R package contains R functions to seamlessly communicate with the VTL engine and aShiny app calledVTLStudio which offers a full Integrated Development Environment.

Users can develop VTL code in the VTL Studio editor (with syntax highlighting and code suggestions):

They can easily browse the results (data and metadata):

They can view the Directed Acyclic Graph that models the transformations they are developing:

It is also possible to send R commands to the engine by means of the RVTL package functions:

With the VTL Engine it is possible to easily work with data stored in many different ways. The so-calledenvironments provide a simple way to connect the engine with the most popular data source types (e.g. CSV files, local R data.frames, SDMX REST providers...). It is also possible to develop custom environments to connect the engine to your specific data storage.

VTL E&E is an Open Source project led by Bank of Italy and built withApache Maven.The project is licensed under theEuropean Public License 1.2.