Technology guru David Lester is determined to make the London Stock Exchange Group more competitive. In his new role as CEO of Turquoise Trading, the pan-European equities trading platform that the LSEG bought in February, Lester plans to align Turquoise’s technology more closely with that of the national exchange, although the two businesses will remain separate.

It’s a huge challenge but one that Lester, 43, who retains his role as the LSEG’s director of information services, knows well: He is already working to replace the trading software used on the main London exchange with a more robust platform designed by Sri Lankan trading technology firm MillenniumIT, which the LSEG bought in 2009.

The LSEG has not a moment to lose: Rival trading platforms Chi-X Europe and BATS Europe have been eating away at its market share at an astonishing rate.