This thesis explores a creation of a very simple real-time embedded operating system for special automotive applications. The work consist the research of specification materials, forming a conception, then actually coding the operating system core, while describing its ideas, solutions, and possibilities of further development. Used interfaces and implemented diagnostics tools are also described along with the in-depth presentation. Configuring and generating content, that is target and application specific, and testing the results are also part of the thesis. The method of satisfying the AUTOSAR (Automotive Open System Architectures) specifications and conceptions, as well as the integration with an already existing AUTOSAR RTE (Runtime Environment) implementation is described. The operating system is ported to four different microcontrollers, and according to device capabilities, even memory protection configuration is used. A comparison between existing embedded operating systems are presented at the end of the thesis.