Zakat is mandatory depending on your specific circumstances. Debt that qualifies towards deduction from Zakat eligibility are amounts you plan on paying back within one lunar year from your Zakat payment date. Once you have deducted your debt value, if the remaining value of your assets go below the Nisab requirement then you would not be liable to pay Zakat. If the value remains above the Nisab requirement, then you are required to pay Zakat on the remaining amount after payment of debt. If you plan on paying back a debt past the one lunar year mark, that value of debt is not eligible for deduction. Similarly, after taking into consideration your debt value, if you remain above the Nisab requirement then Zakat is still obligatory upon you.