Methods, systems, and apparatus, including computer programs encoded on computer storage media, for a composable data model. One of the methods includes receiving an input data file defining: (i) a catalog that defines one or more named elements, one or more named compositions, and one or more named multi-compositions, and (ii) a catalog store that is an instance of the catalog; and generating a data object representing the catalog store in a database, comprising generating data objects respectively representing i) every instance of a named element specified by the catalog store defined in the input data file, ii) every instance of a named composition specified by the catalog store defined in the input data file, and iii) every instance of a named multi-composition specified by the catalog defined in the input data file.