The lower South Island's Civil Construction young contractor of the year, named last week, can drive dump trucks, diggers, bobcats and a good old-fashioned shovel.
But she has yet to persuade employer, Maungatua Contracting, to let her loose with a grader.
That, she appreciates, is a big step up from the other heavy machinery she has mastered, but the company drainage technician has found success everywhere else since joining the company three years ago.
The former gardener and panelbeater, who arrived in New Zealand from Latvia six years ago, says the biggest challenge during her three years with the company has not been the language issue but getting the male-dominated workforce to accept she knows what she is doing.
She is now in command of a drainage crew of three or four working on subdivisions around the Upper Clutha.
As Maungatua director Robert Duncan told the judges for the competition, Ms Onzule has a desire to prove women can make a career in the field "and show doubters are wrong''.
