Note: this is the latest official version 2.96a from April 2002. Now there is an actively developed community driven reboot called gbdk-2020 with compiled versions ready to run on Windows, Linux and Mac OS.
"The GameBoy Developer's Kit (GBDK), is a set of tools that enable to develop programs for the Nintendo GameBoy system, either in C or in assembly. GBDK includes a set of libraries for the most common requirements and generates image files for use with a real GameBoy or with an emulator like VGB or no$gmb. [...]
GBDK features:
From http://gbdk.sourceforge.net
The base version (2.96a) was downloaded from the official site. Although this is the latest version, it was released quite a while ago (back in April 2002).
The code can be compiled in an up-to-date 64-bit Linux environment (at least it is up-to-date here in 2016).
Original sites:
For the build I recommend an Ubuntu 16.04 LTS (you don't even need to install it, the Live system works just fine).
The environment will need a few packages, all of them can be installed using apt-get:
sudo apt-get -y install make gcc g++ bison flex
After downloading the source you can use the Makefile to compile the binaries:
cd /path/where/you/extracted
make
Installing the compiled binaries can be done via make as well:
sudo make install
Compiling the examples:
cd ./gbdk-lib/examples/gb
make
Note: compiling the examples requires you to install the binaries you just built in the previous steps.