Certain embodiments reduce the risks of traditionally programmed algorithms such as syntax errors, unclear logic, and the need for a non-trader programmer to develop the algorithm as specified by a trader by reducing or eliminating the writing of programming code by a user. Certain embodiments provide building block buttons and an algorithm area to define an algorithm. Certain embodiments provide live evaluation of an expression as the algorithm is being defined. Certain embodiments provide a design canvas area and blocks for designing an algorithm. Certain embodiments provide live feedback for blocks as the algorithm is being designed. Certain embodiments provide for initiating placement of an order to be managed by a selected user-defined trading algorithm from a value axis and for displaying working orders being managed by different user-defined trading algorithms on the value axis. Certain embodiments provide a ranking tool.