What next for Amazon as it turns 30?

In the summer of 1994 a job vacancy for software engineers was posted on Usenet, an early precursor to online forums. The company in question planned to “pioneer commerce on the internet”. Applicants needed to be able to design complex systems “in about one-third the time that most competent people think possible”. Résumés could be sent to Jeff Bezos at a Seattle-based startup named Cadabra.

The name didn’t stick—on phone calls “Cadabra” was too easily confused with “cadaver”—but the ambition did. Amazon, which turns 30 on July 5th, has indeed changed the world of online shopping. This year its websites will sell an estimated $554bn-worth of goods in America, reckons JPMorgan Chase, a bank. That gives it a 42% share of American e-commerce, far beyond the 6% captured by Walmart, its nearest online competitor (and biggest retailer overall).