A method for model-based design of safety-critical software is disclosed. The method includes receiving natural-language software requirements, developing a specification model by implementing either semantic modeling or graphical modeling, applying formal requirements analysis to the specification model, auto generating requirements based and robustness test cases from the specification model, developing a design model based on the specification model, applying test cases to the design model, auto-generating source code using the design model, verifying the source code using both test cases and static analysis technology, and compiling executable object code from the verified source code. If a result of the analysis of the software specification or design models is not satisfactory then adjusting the specification or design model to correct any inconsistency, and repeating applying the analysis and test cases. A system for implementing the model-based design and a non-transitory computer readable medium are disclosed.