Most of the source code of HOSPHE (v1.00) is written in Fortran 95. The code consists of several modules that are linked together by using the standard Makefile (see [10]). In general, no special compiler options are needed, except for the optimization flags or check flags for tests. These options are set in the accompanying Makefile, which is now set to work with the G95 compiler that is a free and open-source Fortran 95 compiler (see [11]).
The code HOSPHE (v1.00) also make use of the LAPACK and BLAS linear-algebra libraries that can be obtained from [12,13].