Paul Calder Le Roux (born December 24, 1972) is a former programmer, former criminal cartel boss and informant to the US Drug Enforcement Administration (DEA).
He created E4M, an open-source free Windows disk encryption software program, in 1999, and is sometimes credited for open-source TrueCrypt, which is based on E4M's code, though he denies involvement with TrueCrypt.Le Roux is currently in US custody awaiting sentencing after agreeing to cooperate with authorities in exchange for a lesser sentence and immunity to his most serious crimes.