Numerical simulation of turbulent boundary layers is a challenging task that has prompted the development of different numerical setups. To complement existing techniques, the temporal boundary layer is investigated and found to be a good model for the spatially developing turbulent boundary layer. The remaining temporal development is subsequently eliminated giving a pared-down model yielding the statistically stationary, fully developed boundary layer. A practical use of the temporal boundary layer setup is demonstrated by the addition of free-stream disturbances.