Preheat oven to 350°F (175°C) (Assumption). Grease a 9x5-inch loaf pan (Assumption).
In a bowl, whisk together flour, ground ginger, salt, cinnamon, nutmeg, allspice, and baking soda.
In a second bowl, whisk the beaten eggs with sugar. Add pumpkin puree, melted butter, water, and molasses; whisk until smooth.
Pour wet ingredients into dry ingredients and stir until just combined. Fold in chopped pecans or walnuts if using.
Pour batter into the prepared loaf pan. Bake until a toothpick comes out clean or with a few moist crumbs, about 55–65 minutes (Assumption).
Cool in the pan for 15–20 minutes, then transfer to a rack to cool before slicing.