Abstract: A method of producing an intermediate program representation for an executable personalised medicine treatment program, comprising: providing a domain specific language environment comprising a personalised-medicine programming language syntax and a user interface; selecting a medical knowledge database for a medical condition; receiving user input to build, using the personalised-medicine programming language syntax and the medical knowledge database, a treatment package for implementing one or more treatment modalities for the medical condition, the treatment package including: treatment objectives defining terminating conditions of the one or more treatment modalities; safety guardrails for ensuring patient safety; and treatment titration definitions for modulating the one or more treatment modalities; and validating the treatment package to demonstrate that the treatment objectives, safety guardrails and treatment titration definitions will be satisfied during execution of the personalised medicine treatm