Preheat oven to 350°F (175°C) and grease a 9-inch cake pan.
In a bowl, whisk together flour, baking powder, baking soda, and salt.
In another bowl, combine oil, sugar, almond milk, apple cider vinegar, and vanilla.
Gradually add the dry ingredients to the wet ingredients and mix until smooth.
Gently fold in the blueberries, being careful not to crush them.
Pour the batter into the prepared pan.
In a separate bowl, mix the crumb topping ingredients until crumbly.
Sprinkle the crumbs evenly over the batter.
Bake for 35-40 minutes, or until a toothpick comes out clean.
Allow the cake to cool before slicing and serving.