Alquist 3D is a Greeley, Colorado-based construction technology company that uses robotic 3D concrete printing to build homes, commercial buildings, and infrastructure. Founded in 2020 by Zachary Mannheimer, the company completed one of the first 3D-printed Habitat for Humanity homes in the U.S. and printed an ~8,000-square-foot addition to a Walmart in Athens, Tennessee - billed as the largest 3D-printed commercial structure in the country. In late 2025 it announced a landmark deal to print more than a dozen Walmart and retail buildings, positioning itself to commercialize 3D concrete printing at national scale.
Patrick Callahan is the CEO of Alquist 3D, a Greeley, Colorado company at the front of the 3D concrete printing industry. A West Point-era Army infantry officer turned defense-industry executive, he took the helm in October 2023 and steered the startup from emerging-technology curiosity into a commercial force, landing a landmark partnership with Walmart to 3D print store expansions across the country. He pairs two decades of defense business development - where he captured hundreds of millions in contracts at Critical Solutions International and AirBoss Defense Group - with a mission to make building faster, cheaper, and safer.