Heat the oven to 350°F and lightly grease a 9-inch springform pan.

Combine the graham-cracker crumbs, 1/4 cup granulated sugar, and melted unsalted butter. Press the mixture firmly over the bottom of the prepared pan, bake for 8–10 minutes, and cool slightly.

Place the chopped rhubarb, 1/2 cup sugar, flour or cornstarch, and water in a saucepan. Cook over medium heat for 8–10 minutes, stirring often, until the rhubarb softens and the mixture thickens; cool it to room temperature.

Beat the softened cream cheese and 1/2 cup sugar until smooth. Add the eggs one at a time, mixing gently after each addition, then stir in the vanilla extract.

Pour the cheesecake filling over the slightly cooled crust. Spoon small amounts of the cooled rhubarb mixture over the surface and gently draw a knife through it to form distinct swirls.

Bake for 55–65 minutes, or until the center is nearly set and still has a slight jiggle. Cool the dessert on a rack, then refrigerate it for at least 4 hours before removing the springform ring and slicing.