Note: Packman is outdated. Since 3.1.8 you should use pkgin and pkgsrc. See installing and developing with pkgsrc.
They have more packages than mentioned below.
You can install many of the GNU development tools on MINIX.
You can install GCC via packman. You will also need to install binutils. If you are running MINIX 3.1.4 and above, you will also need to install the corresponding gcc-libs (e.g., gcc-4.1.1-libs) package.
You will need to add /usr/gnu/bin to your $PATH.
You can also install the following tools via Packman. They are very useful if you plan on building third-party programs via MINIX 3: