root@magi3:~# git clone https://github.com/ITensor/ITensor.git

 root@magi3:~# liblapack3 liblapack-dev

 root@magi3:/softs/itensor-3# cp options.mk.sample options.mk

In options.mk :

 #PLATFORM=macos
 #BLAS_LAPACK_LIBFLAGS=-framework Accelerate
 
 PLATFORM=lapack
 BLAS_LAPACK_LIBFLAGS=-L/path/to/lapack/lib -llapack -lblas

 root@magi3:/softs/itensor-3# make

 root@magi3:/softs/itensor-3# cat /softs/modules/compiled/gcc/10.2.1/itensor/3
 #%Module1.0
 proc ModulesHelp { } {
 global dotversion
 
 puts stderr "\tItensor 3"
 }
 
 module-whatis "Itensor 3"
 prepend-path LD_LIBRARY_PATH /softs/itensor-3/lib
 prepend-path LIBRARY_PATH /softs/itensor-3/lib
 prepend-path C_INCLUDE_PATH /softs/itensor-3
 prepend-path CPLUS_INCLUDE_PATH /softs/itensor-3
 prepend-path CPATH /softs/itensor-3
 prepend-path OBJC_INCLUDE_PATH /softs/itensor-3