ETA's demise was not based solely on operating system choice or existence. The Fortran compiler (ftn200) had not changed significantly from the CDC205. This compiler retained vendor-specific programming performance features (known as the Q8* subroutine calls) in an era when supercomputer users were realizing the necessity of source code portability between architectures. Additionally, the compiler optimizations were not keeping up with existing technology as shown by the Japanese supercomputer vendors such as NEC, or at Cray Research and the newer minisupercomputer makers.