Prepare the crust by mixing almond flour, erythritol, nutmeg, cinnamon, and salt. Add melted butter and press into a greased 9-inch springform pan. Bake at 325°F for 10 minutes and let cool.
Make the filling by beating cream cheese and erythritol until smooth. Add eggs one at a time, then mix in vanilla, rum extract, and nutmeg until combined.
Pour the filling over the cooled crust and bake for 45-50 minutes until the center is set but slightly jiggly. Turn off the oven and let cool for 1 hour.
Chill the cheesecake in the refrigerator for at least 4 hours or overnight. Whip heavy cream and spread over the top before serving.