Not only is sorting a Python list implemented in C, the algorithm was sufficiently impressive to be picked up by Java for non-primitives: http://hg.openjdk.java

Not only is sorting a Python list implemented in C, the algorithm was sufficiently impressive to be picked up by Java for non-primitives: http://hg.openjdk.java.net/jdk7/tl/jdk/rev/bfd7abda8f79 http://hg.openjdk.java.net/jdk7/tl/jdk/rev/bfd7abda8f79 The reason it's for non-primitives is because it's optimized for sorting lists where comparison is relatively expensive , such as the dereferencing Python does on every item and Java does for non-primitive items. Thanks for putting the effort in and testing it! Very interesting results.