Place the crackers on a parchment-lined baking sheet. Cut each slice of cheese into 4 squares. Finely chop the cucumber.
Place the cheese on the crackers. Top with mustard and ketchup and some chopped cucumber.
Cut the sausages into thick slices and place them on top of the cucumber.
Place the snack on crackers, with cheese and sausages, in an oven preheated to 180 degrees, cook a simple snack on crackers for 10-12 minutes, until the cheese melts.