Eir is an IRC client bot framework, written primarily for freenode utility functions. It is, however, highly extensible using C++ or Perl, and is used by other projects as well.
If you just want to know how to build and install it, do the following after
making sure you have the obvious pre-reqs (build-essential, libperl-dev)
installed:
git submodule init
git submodule update
autoconf
./configure --prefix=SOMEWHERE
make
make install
To install on FreeBSD, you will need g++ and gmake, so something like this:
# if not already available do the following:
sudo pkg install gcc6 gmake
git submodule init
git submodule update
autoconf
./configure --prefix=SOMEWHERE
CXX=g++6 gmake
gmake install
Then go to SOMEWHERE/etc, and write eir.conf. There is an example config file installed.
Eir comes with a few perl script modules, including Bantracker.pl, and a module for sasl-auth login. You will want to copy these to your install location