Pelle Braendgaard has the textbook bio of an old-guard programmer. At 12, he often went to his local computer store in Denmark to write BASIC code on an eight-bit Sinclair ZX Spectrum. In 1993, he stumbled across Mosaic, the first graphical web browser, while aimlessly cruising the UNIX command line on a university computer. He quickly fell in love with the web, and found a job as the webmaster for AltaVista, a pioneering search engine.

“In the very early days, you really had to figure it all out yourself,” Braendgaard says, in an accent that floats between Danish and American. “All of us who were developing back then, we had to learn everything...there weren’t good libraries. There weren’t good developer tools.”

Gabe Nicholas is a graduate student at the UC Berkeley School of Information focusing on the intersection of technology and society. Sign up to get Backchannel's weekly newsletter.

The web has matured since then, but Braendgaard has moved on. Today, he’s writing distributed applications, or “DApps,” for Ethereum—a cryptography-based technology that’s as green a field as the 1990s web once was, offering the same tingle of novelty and a similar chance to make an impact.

If people know Ethereum at all, it is as Bitcoin’s hip, experimental cousin. If they know one thing about it, it is that the price of Ether, the coin underlying Ethereum, has skyrocketed by a factor of 20 over the last six months. But the ensuing get-rich-quick mania has led many to overlook Ethereum’s more lasting significance. More than a new type of digital currency, it is a new type of distributed computer—one that no one controls but inside which anyone can see. On this computer, a new generation of applications, called “DApps,” is being born.

How can Ethereum be a cryptocurrency and a computer at the same time? Instead of running on a laptop or a server, it runs on thousands of individual computers at once, all kept in sync with blockchain technology. In its simplest form, a blockchain is an ordered list of items upon which all of these computers agree. On Ethereum, that list is made up of programmable computer states (think ones and zeros). Anyone can pay currency (Ether, not dollars) to run their code on—and thus change—the state of the computer. Miners enter their machines into a random mathematical race to win the chance to choose which code will run next (i.e., to add the next block of ones and zeroes to the list) and collect the associated fees.

This system is called the Ethereum Virtual Machine (EVM), or colloquially, the “world computer.” Code is run publicly, but users are pseudonymous. It’s like Amazon Web Services, except instead of Amazon as the seller and users as the buyer, users can play either role. No individual controls the system. That makes Ethereum something genuinely new—something unprecedented.

Decentralized apps, or DApps, are programs that run on the world computer. “Run,” however, might not be the right word, because Ethereum-the-computer is dreadfully slow, and writing code for it is like turning back the digital clock a few decades. Computation on the EVM right now is far too expensive and inefficient to run a modern web-based service like Twitter. Storing even a single profile picture would cost hundreds of dollars, and today the network can only run about seven transactions per second. (For comparison, Facebook runs 25,000 transactions per second on searches alone.) Software changes can speed things up some, but Ethereum is always going to be slower than more conventional computing.

It’s a cumbersome system, but that’s not deterring developers from writing Ethereum programs. They’re attracted to what the platform earns by spending all those extra resources. DApps are small, interconnected scripts that transfer currency and connect users. They are good at coordinating lots of computers to perform tasks in exchange for currency without any central oversight. This decentralization is Ethereum’s biggest draw. DApps do not need to trust in the benevolence of central administrators like Amazon to run code, or in payment systems like PayPal or banks to exchange currency.

Blockchain theorists have a name for this decentralized protection from outside meddling: They call it “trustlessness,” and it is at the core of many DApps. (The term is confusing, because it sounds like a label for something you can’t trust. But what it’s really saying is, because you can trust the cryptography and the blockchain, you don’t have to take anyone’s word for anything.) The "Hello, World!” of Ethereum DApp development—the starter exercise programmers use to learn how a system works—is a voting DApp. If a voting DApp were used in say, a presidential race, the DApp could autonomously count the votes and determine a winner. All votes would be anonymous, but anyone could see the code that counted them and the system would be immune to meddling from, say, Russian oligarchs. Braendgaard is the lead engineer on a different kind of DApp called uPort, which uses trustlessness to let users manage their own identities. Users can prove their identity with other applications, but, unlike when signing into an app via Facebook or Google, they can do so without trusting a centralized provider.