Abstract: Methods and apparatus, including computer program products, for defining, through a no-code graphical user interface, a sequence of functionality blocks defining a process to be performed by a system integration platform, and wherein each functionality block is configured to execute an operation on one or more input parameters to the functionality block to produce one or more output parameters from the functionality block. The system integration platform receives, source system data that includes one or more input parameters for a first functionality block. Data from the one or more source systems is processed by traversing the functionality blocks in a unidirectional manner from a beginning to an end, where one or more output parameters from a functionality block serves as input parameters for one or more immediately subsequent functionality blocks. A last functionality block outputs destination system data to be ingested by the one or more destination systems.