German e-commerce pioneer Ralf Wenzel’s quick-delivery retail platform Jokr, which has gone live in seven countries since launching barely four months ago, said on Tuesday it had raised $170 million from investors to power growth.

The Delivery Hero and Softbank veteran has styled the business as an “Amazon on steroids” and, with revenue doubling every two weeks, is on a high-speed mission to bring 15-minute delivery to the Americas and Europe.

“We truly believe that the world needs a new Amazon,” Wenzel said. “There is an opportunity to create a faster Amazon, a more personalized Amazon, a more sustainable Amazon and a more local Amazon.”

The bumper Series A funding round was led by Silicon Valley investor GGV Capital, London-based Balderton Capital, and the prolific Tiger Global Management.

Tiger Global, which chipped in to Jokr’s seed round earlier this year, has also backed quick commerce startups including Getir and Wolt.

The venture capital being lavished on quick-commerce startups seeks to capture a seismic shift in consumer habits, as people increasingly order via smartphone app and take delivery in less time than it takes to pop out to the local shop.

Wenzel said the typical new Jokr customer will buy just one or a few items to try out the service. Many, within a short space of time, go on to replace their traditional grocery shop by making several larger orders a week.

“We grew significantly faster than what we thought, but the fast growth was not on the back of significant burn or discounting,” Wenzel said in an interview.

“The fast growth was backed by a lot of organic momentum – very strong word of mouth, very strong retention rates, very strong stickiness.”

By acting as a retailer rather than a marketplace, Jokr can order more merchandise directly – cutting out middlemen and achieving strong margins that mean its earliest locations are already breaking even on a fully-loaded cost basis.

In the Americas, Jokr is now present in New York, where it is headquartered, as well as in Sao Paolo, Mexico City, Bogota and Lima. In Europe, it has launched in Warsaw and Vienna – avoiding higher-cost markets like London and Paris – with more rollouts to come.

“We are already able to show to investors that it’s not only a high-growth business but also a business that we are able to run efficiently,” said Wenzel.