I recently read Igor Shadurin's article Dive Into dApps. In it, he defines a dApp (or decentralized application):

The commonly accepted definition of a dApp is, in short, an application that can operate autonomously using a distributed ledger system.

From Dive Into dApps
Referenced 2023-11-12T15:39:42-0500

I think that definition is too specific to blockchains. Blockchains are an implementation choice and there are other ways to solve the problem. That said, if you're looking to create a dApp with a smart contract, then Igor's article is a nice place to start.

Let's start with the goal and work backwards from there. The goal of a dApp is to give people control over their apps and the data in them. This is not how the internet works today. As I wrote in The CompuServe of Things, the web and mobile apps are almost exclusively built on a model of intervening administrative authorities. As the operators of hosted apps and controllers of the identity systems upon which they're founded, the administrators can, for any reason whatsoever, revoke your rights to the application and any data it contains. Worse, most use your data for their own purposes, often in ways that are not in your best interest.

dApps, in contrast, give you control of the data and merely operate against it. Since they don't host the data, they can run locally, at the edge. Using smart contracts on a blockchain is one way to do this, but there are others, including peer-to-peer networks and InterPlanetary File System (IPFS). The point is, to achieve their goal, dApps need a way to store data that the application can reliably and securely reference, but that a person, rather than the app provider, controls. The core requirement for achieving control is that the data service be run by a provider who is not an intermediary and that the data model be substitutable. Control requires meaningful choice among a group of interoperable providers who are substitutable and compete for the trust of their customers.

I started writing about this idea back in 2012 and called it the Personal Cloud Application Architecture. At the time the idea of personal clouds had a lot of traction and a number of supporters. We built a demonstration app called Forever and later, I based the Fuse connected car application on this idea: let people control and use the data from their cars without an intermediary. Fuse's technical success showed the efficacy of the idea at scale. Fuse had a mobile app and felt like any other connected car application, but underneath the covers, the architecture gave control of the data to the car's owner. Dave Winer has also developed applications that use a substitutable backend storage based on Node.

Regular readers will wonder how I made it this far without mentioning picos. Forever and Fuse were both based on picos. Picos are designed to be self-hosted or hosted by providers who are substitutable. I've got a couple of projects tee'd up for two groups of students this winter that will further extend the suitability for picos as backends for dApps:

• Support for Hosting Picos—the root pico in any instance of the pico engine is the ancestor of all picos in that engine and thus has ultimate control over them. To date, we've used the ability to stand up a new engine and control access to it as the means of providing control for the owner. This project will allow a hosting provider to easily stand up new instance of the engine and its root pico. For this to be viable, we'll use the support for peer DIDs my students built into the engine last year to give owners a peer DID connection to their root pico on their instance of the engine and thus give them control over the root pico and all its decedents.
• Support for Solid Pods—at IIW this past October, we had a few sessions on how picos could be linked to Solid pods. This project will marry a pod to each pico that gets created and link their lifecycles. This, combined with their support for peer DIDs, makes the pico and its data movable between engines, supporting substitutability.

If I thought I had the bandwidth to support a third group, I'd have them work on building dApps and an App Store to run on top of this. Making that work has a few other fun technical challenges. We've done this before. As I said Forever and Fuse were both essentially dApps. Manifold, a re-creation of SquareTag is a large dApp for the Internet of Things that supports dApplets (is that a thing?) for each thing you store in it. What makes it a dApp is that the data is all in picos that could be hosted anywhere...at least in theory. Making that less theoretical is the next big step. Bruce Conrad has some ideas around that he calls the Pico Labs Affiliate Network.

I think the work of supporting dApps and personal control of our data is vitally important. As I wrote in 2014:

On the Net today we face a choice between freedom and captivity, independence and dependence. How we build the Internet of Things has far-reaching consequences for the humans who will use—or be used by—it. Will we push forward, connecting things using forests of silos that are reminiscent the online services of the 1980's, or will we learn the lessons of the Internet and build a true Internet of Things?

From The CompuServe of Things
Referenced 2023-11-12T17:15:48-0500

The choice is ours. We can build the world we want to live in.