At the occasion of the 20th anniversary of the first commercial publication of Xpress Mosel (2001) this contribution takes the audience through the major phases of its development, stressing as the two main drivers behind its design and evolution user requirements/usage patterns and technological (hardware) advances.
Particular focus is directed at the phase preceding the first publication during which the fundamental questions of whether, why, and how to replace an established software (namely Mosel's precursor mp-model, commercialised by Dash Associates since 1983) had to be addressed.