Insulin pills have long been a kind of Holy Grail for people living with diabetes. A research team at MIT believes it may have taken an important step toward that dream with a new blueberry-sized capsule made of compressed insulin.

Once ingested, water dissolves a disk of sugar, using a spring to release a tiny needle made up almost entirely of freeze-dried insulin. The needle is injected into the stomach — which the patient can’t feel, owing to a lack of pain receptors in the stomach. Once the injection has occurred, the needle can break down in the digestive tract.

The pill is able to orient itself once swallowed, in order to make sure it injects in the right spot. That bit was apparently inspired by tortoise shells.

According to MIT, “The researchers drew their inspiration for the self-orientation feature from a tortoise known as the leopard tortoise. This tortoise, which is found in Africa, has a shell with a high, steep dome, allowing it to right itself if it rolls onto its back. The researchers used computer modeling to come up with a variant of this shape for their capsule, which allows it to reorient itself even in the dynamic environment of the stomach.”

So far, the team has been testing the pill successfully in pigs, delivering up to 300 micrograms of insulin in a go. No word on how long it might take to arrive in pharmacies.