and, two questions with building process:

• is here exists easy way to "remap" system to use not-installed pike ,

i.e. some from ~/apps/Pike-v7.8.680

You can run "make hilfe" from the build tree to use the non-installed pike. As you will see, there are a number of extra command line flags needed to make it work correctly.

However, if you just want to run pike from somewhere in your ~, you can install it there. The simplest way is to run "make install_interactive", and then select something like "/home/oleksii/apps/Pike" as the prefix.

• is it possible to build pike without pike installed ?

Yes, the source dists can be built without pike installed. But to build from git you need to have pike installed.