Shayama Sen was the Chief Fabricator, and therefore head of the starship foundries on the planet Ix during the advent of Kralizec.
The Mathematical Compiler[]
Under the unknown influence of the chief Enhanced Face Dancer Khrone, Sen listened to Khrone, who was posing as one of Sen's long-time research assistants. Khrone introduced the Ixian technological society to an advanced machine which could fold space with the accuracy approaching that of a Guild Navigator, which Sen dubbed a mathematical compiler. The mathematical compiler was in actuality a device from the reborn Thinking Machine empire, and Khrone had been ordered by Omnius and Erasmus, to have the device "invented" and "discovered" on Ix.
Afer six years of Khrone' "intensive research" at the Ixian foundries, Sen showed his assistant's device to representatives from CHOAM and the Administrator branch of the Guild. CHOAM saw the compilers as a way to garner huge profits, and the Administrators from the Guild decided to "do away" with their Navigators a short time later. The compilers were so efficient that Sen even offered them to Mother Commander Murbella of the New Sisterhood, who had a monopoly on the spice Melange.
Killed by Khrone[]
In just a few short years, thousands of vessels with sabotaged mathematical compilers were installed on every vessel shipped out from Ix, as Khrone lead his Face Dancers assistants and workers to install the traitorous devices. After most of the human fleet and cargo ships were delivered to their destinations, Khrone killed Sen, and secretly took his place as leader of the Ixians. It is not know if Khrone faked Sen's death later, when Khrone was permanently re-called to the capital of the Thinking Machine Empire, Synchrony, to deliver the ghola of Paul Atreides, Paolo, to the Cathedral.
Later, on the Day of Kralizec, each and every vessel installed with a mathematical compiler had its' secret 'off' switch activated by the approaching Thinking Maschine armada. Sadly, Sen had played a major and unwitting role of traitor, as the last-ditch human fleet above Junction and Chapterhouse, was left vulnerable to the first wave of the million-vessel Thinking Machine armada.