The SmallEiffel compiler makes intensive use of aliasing in order to achieve very good performance both in terms of memory and execution time. This technique is very appropriate for compilation, but can also be applied to a wide range of applications. Thanks to the design by contract capabilities of the Eiffel language, aliasing can be handled very safely. The singleton pattern appears to be crucial in implementing alias provider objects. We propose an efficient implementation of this pattern made easy by some Eiffel idioms.