Programmable Logic Controllers (PLCs) are used to control large scale systems with thousands of I/O devices. Writing and maintaining the logic for each of these is a cumbersome task, which is well suited to be abstracted through templating. For this purpose, CERN developed the Unicos Application Builder (UAB). While UAB is successful at templating, it provides no guarantees over the validity of the outcome, leading to erroneous generated code. This is where SCL-T comes in. It builds on the foundation of UAB to facilitate meta-programming for Siemens’ SCL. Unlike its predecessor, it guarantees syntactic correctness and also draw conclusions regarding the semantic validity of the generated code. Its architecture has been designed in such a way that support for other PLC languages can be added using the same meta-language, reducing the cost of a having a meta-programming language tailored for a specific PLC language.