Backley, who served as the bank's chief technology officer prior to its merger with St George, pioneered several of Westpac's most ambitious technology projects.
Under Backley's watch, Westpac's Internet banking system scaled to peaks of 700,000 sessions a day and 6000 concurrent users.
He also rolled out the bank's wildly successful Blackberry strategy.
His was also the public face of a large traditional Australian enterprise prepared to invest in and experiment with new Web 2.0 tools such as Facebook and Second Life.
Last month Backley informed the Enterprise 2.0 Forum in Sydney that he was no longer CTO of the bank, but was acting as general manager of application development. "Read into that whatever you will," he said.
Backley is currently completing a study on technology's effect on work/life balance.