In a food processor, grind up the crackers until fine crumbs form. While the motor is running, drizzle in the melted butter and blend until well combined.

Line a 9-inch pie dish with two layers of plastic wrap. Transfer crumb mixture to pie dish and press firmly and evenly along the bottom and up the sides, using a flat-bottomed dry measuring cup to help press the crumbs neatly. Cover with plastic wrap and refrigerate while you prepare the filling.

Pour pineapple juice into a small bowl. Sprinkle gelatin evenly over the surface, stir to combine, and set aside to bloom.

In a medium non-reactive saucepan, combine the sugar, butter, lemon zest, lemon juice, sumac, and salt. Heat over medium, stirring occasionally, until the butter melts and the mixture just starts to simmer (do not boil), about 6 minutes.

Meanwhile, whisk the whole eggs and egg yolks in a medium bowl. Turn off burner. While whisking eggs in bowl, gradually add hot sugar mixture to bowl.

Transfer egg mixture to saucepan and cook over medium heat, whisking constantly, until the lemon curd becomes very thick and big slow bubbles begin to rise to the surface, 5 to 8 minutes.

Immediately remove the saucepan from the heat, add the bloomed gelatin mixture, and whisk until thoroughly combined.

Pour the filling through a fine-mesh sieve into another bowl, stirring the filling to allow the mixture to strain (do not press), then pour into the refrigerated pie crust.

It may not all fit into the pie; cover and chill any remaining filling to snack on. Refrigerate the pie until chilled, at least 4 hours or up to overnight.

When ready to serve, garnish the pie with your choice of fruit. Cut the pie into wedges and use the plastic-wrap lining to help lift slices out of the pie dish.