Preheat the oven to 350 degrees F (175 degrees C). Line a baking sheet with parchment paper.

Mix almond flour, walnuts, flax seed meal, and salt together in a bowl until well combined. Add water and olive oil; mix until dough is moist and holds together.

Turn dough onto the prepared baking sheet. Place a second piece of parchment over the dough and use a rolling pin to roll it into a 1/16-inch-thick rectangle. Remove the top piece of parchment and cut the sides of dough to make an even rectangle. Add excess dough to corners or one end of the rectangle and re-roll to a uniform thickness.

Cut dough into 1-inch squares using a pizza cutter, keeping dough still attached.

Bake in the preheated oven until the outside edges of dough are browned, about 15 minutes. Cool crackers on the baking sheet, then break into squares.