The yield curve represents market supply and demand implied expectations of future interest rates and is calibrated from the most liquidly traded interest rate derivatives like cash deposits, forward rate agreeents, swaps and futures. Due to the daily margining mechanism of futures contracts, interest rate futures require the substraction of a convexity adjustment in order for them to be used in curve calibration. It is common practice to use externally computed convexity adjustments, which treats the convexity adjustment as a black-box parameter. We will argue the inherent relationship between the convexity adjustment and cap/floor volatility smiles and derive a nested calibration algorithm for the simultaneous calibration of the yield curve to futures and the convexity adjustment to cap/floor volatility surfaces. This introduces dependencies of the yield curve to option volatilities and we will argue that for simple interest rate derivatives the implied vegas are negligible. .