Is there a way that I can make
$ make
default to:
$ make -j 8
?
Set the environment variable MAKEFLAGS to -j 8. If you are using csh or tcsh, you can do this with setenv MAKEFLAGS '-j 8'. If you are using bash, you can do this with export MAKEFLAGS='-j 8'. You might wish to put this command in your shell's start-up file, such as .cshrc or .bashrc (in your home directory).
Caution: Setting a default like this will apply to all invocations of make, including when you "make" a project other than your own or run a script that invokes make. If the project was not well designed, it might have problems when it is built with multiple jobs executing in parallel.