On-demand delivery/courier service Postmates has just undergone a major expansion. Today it announced that it’s in 10 new cities, bringing the total number of markets to 40. Cities that are now online include Baltimore; Palm Springs, California; Pittsburgh; St. Louis; Milwaukee; Oklahoma City; Kansas City; Columbus, Ohio; and Jersey City, New Jersey.

As a treat to its new users (or simply to entice them to download the app), Postmates will deliver Chipotle free to its customers in the new markets now through September 30.

This rapid growth comes on the heels of its expanding partnerships with major brands, such as Chipotle. Earlier this week it announced its relationship with Walgreens. So besides getting local goods delivered, now customers can get drugstore items, coffee, and even burritos delivered right to their door in under an hour.

We’re told that to date, the company has a fleet of nearly 15,000 riders and drivers and has completed more than 4 million deliveries from 65,000 merchants across the country. In 2015 alone, Postmates has expanded to 25 cities throughout the U.S.

What’s interesting about this growth is that Postmates appears to be targeting cities with at least a thriving tech ecosystem, such as Baltimore and St. Louis. However, while tackling 10 new cities at once is certainly a monstrous task, a Postmates spokesperson told VentureBeat, “We’ve already proven Postmates at scale and we have the ability to launch new markets and get them up and running quickly and efficiently. With 30 successful launches complete, our launch team is incredibly agile.”