What is Genero Report Writer (GRW)? Genero Report Writer provides a means for creating high-quality reports. GRW overview With Genero Report Writer, you create a report application that serves as a data model. The data is retrieved from a data source (typically a database) and streamed to a layouter, which lays out the data according to the specifications of a report design document. GRW runtime architecture At runtime, various software components work together to produce a Genero report.