A variety of agent-oriented programming languages based on concepts such as beliefs and goals has been proposed in the literature. Even though most of these languages now come with interpreters implemented in e.g. Java and can be used to write software agents, there is little work reporting how to implement such languages or to identify a core instruction set that would facilitate such implementation. In this paper we introduce a compiler for the language GOAL into the framework of Jazzyk Behavioural State Machines. The result is a translation of key agent concepts such as beliefs and goals into Jazzyk which lacks these notions, thus providing some evidence that it may provide a sufficient instruction set for implementing agent programs. Moreover, arguably, the implementation strategy used can be applied also to other agent programming languages.