There has been an explosion in the number of new databases in the recent years - it is easier than ever to build a new database system. In this talk we will look at the components of the DBMS stack, how they can be reused and/or replaced. Using examples of existing commercial and academic databases on the market, we will see how a database system can be composed from diferent existing components, or how novel ideas can be implemented by replacing one or more components in the existing system. Speakers Biography: Mosha Pasumansky is the CTO of Firebolt Analytics. Previously he worked on BigQuery in Google, on Cosmos in Microsoft Bing, and on Microsoft Analysis Services. Mosha is the co-inventor of MDX query language. He received a M.Sc. in Computer Science from the University of Washington. Benjamin leads the query processing teams at Firebolt. The teams are working on query optimization, distributed query execution, and Firebolt's single-node runtime. Benjamin first fell in love with database systems while studying computer science at the Technical University of Munich.