Heat olive oil in a small skillet over medium heat. Stir in garlic and thyme; cook 1 minute and stir into mayonnaise. Transfer aioli to a small bowl, cover and refrigerate until serving.
Wipe out skillet and add ketchup and curry. Bring to a simmer and cook 1 minute. Transfer to a small bowl, cover and refrigerate until using.
Heat canola oil in a large heavy-bottomed pot to 325°. Rinse potatoes in a bowl filled with cold water until water is clear (which means the starch is gone). Transfer fries to paper-towel-lined baking sheets and pat dry with additional paper towels. In 4 batches, fry potatoes at 325° for 5 minutes. (Make sure oil returns to 325° before adding each batch.) Remove with a slotted spoon or mesh strainer to fresh paper-towel-lined baking sheets.
Increase oil temp to 375°. Again, in 4 batches, fry 3 minutes, until golden brown. Remove to baking sheets and sprinkle with salt. Serve hot with aioli and curry ketchup.