I suppose you'd do it the same way any North Korean operative would. They'd offer you training on how to bypass the controls. They'd get you to exfiltrate the code and the product roadmap. They'd have someone more skilled suggest a plausible backdoor as part of an innocent change, like the xzutils one.
As for how they'd force you, just like any intelligence agency, they'd start with carrots. They'd offer you money, or the chance to feel you were serving your country (both are free to the Australian government, and likely more effective than a double ration of wheat). They'd have you do very innocent, justifiable things at first. They'd work their way up to higher demands. If you got cold feet, they'd tell you you were in too deep. They'd then consider the sticks. They'd threaten to expose your spying, or release some other compromat. They'd arrest you or a family member on a he-said-the-cops-said enemy-of-the-people crime like drugs, child pornography or terrorism, and make it clear that only your full cooperation would see a release.
Nobody thinks the Australian government relies on this kind of thing as much as NK, and the checks and balances of a democracy make it too expensive to do this at an industrial scale. But you'd be foolish if you thought the state doesn't have these capabilities, and the complete willingness to use them for matters of national security, and the ability to make it "legal", perhaps by pardoning people or not cooperating with any court.