Open a root terminal and issue the following commands:

lenny:/home/hfp# apt-get -y install build-essential
lenny:/home/hfp# apt-get -y install bison
lenny:/home/hfp# apt-get -y install flex
lenny:/home/hfp# apt-get -y install automake
lenny:/home/hfp# apt-get -y install fakeroot
lenny:/home/hfp# apt-get -y install doxygen
lenny:/home/hfp# apt-get -y install yodl
lenny:/home/hfp# apt-get -y install gettext
lenny:/home/hfp# apt-get -y install git-core
lenny:/home/hfp# apt-get -y install subversion
lenny:/home/hfp# apt-get -y install libncurses5-dev
lenny:/home/hfp# apt-get -y install zlib1g-dev

Note: From now on, all commands will be executed as the normal hfp user, no root privileges required.

Additional packages

Although not necessary, I also install the following packages:

lenny:/home/hfp# apt-get -y install ssh
lenny:/home/hfp# apt-get -y install vim

Next: Install buildroot and create the initial hfproot filesystem