When it comes to software engineering for machines and systems, OEMs are faced with new challenges. In addition to increased efficiency in PLC automation, they are increasingly interested in realizing customized software functions to set themselves apart from the competition. This is where integrating modern information technologies opens up new possibilities in production. IEC 61131-3-based engineering is reaching its limits here. Therefore, Bosch Rexroth is now using Open Core Engineering to connect PLC and IT automation and give developers a greater degree of freedom in software engineering. OEMs can flexibly access the control core of the system solutions IndraMotion MLC and IndraLogic XLC from applications based on high-level languages. This allows them to realize customized solutions independently and more easily. Open Core Engineering brings the requirements from previously separated engineering worlds together in one integrated solution. At its center are software tools and function toolkits that build entirely on open standards and technologies. The new interface enhances the software engineering - which until now has been focused on PLC automation - enabling it to work with applications based on high-level languages. With numerous function libraries which are adapted to different development environments it is now possible to have functions directly access the control core. This allows OEMs to realize customized software functions in-house and to integrate IT technologies based on high-level languages into their automation solutions. Specific examples are the integration of simulation tools or the use of smart devices with native apps. Moreover, the interface makes it possible to integrate production machine functions and data out of IT-based applications such as management execution systems.