SIR
SIR stands for Stokes Inversion based on Response functions (SIR), a general-purpose code capable of dealing with gradients of the physical quantities with height. It admits one and two-component model atmospheres.
Download
To install SIR, download it from here, gunzip and untar the file. The directory "manual" contains a somewhat outdated user's guide which you should read for basic information on compilation of the code, input/output files, etc. We strongly recommend you to use the Intel Fortran 95 compiler, as it produces the fastest executable. For any question, send a mail to brc@iac.es.