Glennie subsequently worked at Atomic Weapons Research Establishment (AWRE) where he was responsible in the early 1960s in developing FORTRAN compilers for several large computers inc. IBM 709, IBM 7090, IBM 7030 ("Stretch") and also ICT Atlas.
During the early 1960s, Glennie worked at AWRE to develop FORTRAN compilers for various large computers like IBM 709, IBM 7090, IBM 7030 ("Stretch"), and ICT Atlas.