How to add own cpp-files to Makefile I successfully managed to compile bitcoind using the shipped configure script/makefile. Now I want to code something myself and added a folder inside the src directory. The problem now: how do I add my cpp files to the Makefile? When compiling, I get undefined references to functions I implemented inside my cpp files. When looking inside my folder, there are no .o files or anything similar, so I assume they are not compiled. I am completely novice to autoconf/automake and have no idea how to add something to those complicated makefile/configure scripts.. 

Best wishess to all of you
Bitcoin uses the autotools build system in order to build the source code.  It is a very powerful, yet notoriously confusing system.  You will need to edit the Makefile.am file to include the source files you want to build, and to point the linker to compiled sources.  You will then need to rerun parts of the build system (automake, ./configure, etc...) in order to regenerate Makefile.

The specifics for how to do this are difficult to say, since you will need to determine which parts of the system your new code depends on, and which parts depend on your new code.  I suggest reading up on autotools, determining what is needed for your particular code changes.