QtiSAS fitting interface is done as simple as possible close to c/c++ basics. It allows to use already existing codes of fitting functions. For example, here the catalog of implemented SasView functions is located. In SasView most of functions are combination of c++ and python codes. You could copy/paste c++ code to a new QtiSAS function in Fit.Compile interface. But here we show how to make “block” function, which will be easy to use as a block of a complicate function…

In Fit.Compile there is integrated tools to “mix” codes created in SasView, SasFit, QtiKW/QtiSAS, Fortran. It's planned to upload different examples of integrations of different blocks.