Uber has today announced the public launch of its UberRUSH API, letting any developer offer delivery of their products through Uber .

UberRush launched back in October of 2015, offering same-day delivery of items through the app. It was a basic courier service, with deliveries via both Uber cars and bike messengers.

In January, the company took it a step further with the launch of a private API, letting retailers bake same-day delivery right into their apps and websites.

These partners included Nordstroms, 1800Flowers, Google Express and others.

Today, however, Uber can power same-day delivery for almost anything thanks to the UberRUSH open API.

From Uber’s blog post:

With a variety of endpoints and features, the RUSH API acts as a simple solution for companies looking to build or streamline last-mile logistics. Now anyone can build on-demand delivery right into an existing business – or dream up something completely new.

To kick off the launch of the API, Uber is holding workshops the week of June 27 in Chicago, San Francisco, and New York.

Uber has been working on this for quite some time.

In April of 2015, we reported on leaked documents that showed plans for a wide-scale merchant delivery program. This program would allow an Uber driver to pick up an item at a store and tuck it in the trunk, pick up a person and complete a fare, and drop off the original item at its final destination in a single trip. Two birds, one Uber driver.

Though Uber has been putting this plan into motion over the past year, it’s only now that it is finally being unleashed on the public.

Of course, this puts Uber even more squarely in the ring with Postmates, which has integrated directly with a number of retailers like Starbucks, Chipotle, and Apple. Plus, Postmates has been getting more aggressive with non-food retail deliveries.

Still, Uber’s network of driver partners and its powerful logistics platform could take the on-demand economy to a whole new level.