Hello, ksandro, you wrote: K> For example: K> * video Handling in real time. And users want that was fullHD and not . I suppose, on pure Si. Difficult abstractions in such task are not necessary, and only are hindered. K> * Trejding. Traders very much do not love when they press the button to buy, and happens at the price which strongly differs from the price which they see on . Is still algorithmic , there all is much more rigid (there than 20 microseconds it already slowly). In trading I not the big expert but how much I can judge, there am important not only speed, but also nontrivial data handling. It seems to me, language of type Ocaml would approach much more. It fast enough, and at the same time on it it is convenient to work with difficult data structures. K> * toys. Not a tetris on , and present 3D games. Gamers love the beautiful drawing, and do not love when game . Besides, not the expert. But I think, game is quite logically divided on fast, and rather simple, a part, and slow, but difficult. At such sharing it would be more convenient to write in two different languages. But this approach does not enjoy wide popularity. More likely from fear, than because of real complexities.