BLOCKSTACK

Blockstack is the new decentralized internet.

With Blockstack, users control their data and apps run on their devices. There are no middlemen, no passwords, no massive data silos to breach, and no services tracking us around the internet.

The applications on blockstack are server-less and decentralized. Developers start by building a single-page application in Javascript, Then, instead of plugging the frontend into a centralized API, they plug into an API run by the user. Developers install a library called blockstack.js and don't have to worry about running servers, maintaining databases, or building out user management systems.

Personal user APIs ship with the Blockstack app and handle everything from identity and authentication to data storage. Applications can request permissions from users and then gain read and write access to user resources.

Data storage is simple and reliable and uses existing cloud infrastructure. Users connect with their Dropbox, Google Drive, S3, etc... and data is synced from their local device up to their cloud.

Identity is user-controlled and utilizes the blockchain for secure management of keys, devices and usernames. When users login with apps, they are anonymous by default and use an app-specific key, but their full identity can be revealed and proven at any time. Keys are for signing and encryption and can be changed as devices need to be added or removed.

Under the hood, Blockstack provides a decentralized domain name system (DNS), decentralized public key distribution system, and registry for apps and user identities.

This is your name & identity that is registered in the .id namespace on Blockstack. Your personal data and storage are built around this ID. Apps that want to access your data use your permission and identity to find it.

A decentralized internet is one where users don't need to trust any intermediaries or remote services. We envision a world where users control their own data, and power flows back to the users. Reducing the friction to deploying new Blockstack nodes is an important step towards that mission.

Developers can now build Web applications where:

you own your data, not the application
you control where your data is stored
you control who can access your data
Developers can now build Web applications where:

you don't have to deal with passwords
you don't have to host everyone's data
you don't have to run app-specific servers
Right now, Web application users are "digital serfs" and applications are the "digital landlords". Users don't own their data; the app owns it. Users don't control where data gets stored; they can only store it on the application. Users don't control access to it; they only advise the application on how to control access (which the application can ignore).

Blockstack applications solve both sets of problems. Users pick and choose highly-available storage providers like Dropbox or BitTorrent to host their data, and applications read it with the user's consent. Blockstack ensures that all data is signed and verified and (optionally) encrypted end-to-end, so users can treat storage providers like dumb hard drives: if you don't like yours, you can swap it out with a better one. Users can take their data with them if they leave the application, since it was never the application's in the first place.

At the same time, developers are no longer on the hook for hosting user data. Since users bring their own storage and use public-key cryptography for authentication, applications don't have to store anything--there's nothing to steal when they get hacked. Moreover, many Web applications today can be re-factored so that everything happens client-side, obviating the need for running dedicated application servers.

The application itself should not run application-specific functionality on a server. All of its functionality should run on end-points. However, the application may use non-app-specific servers with the caveat that they must not be part of the trusted computing base. This is the case with storage systems like Amazon S3 and Dropbox, for example, because Blockstack's data is signed and verified end-to-end (so the storage systems are not trusted to serve data). Serverless can also mean applications where some amount of server-side logic is still written by the application developer but unlike traditional architectures is run in stateless compute containers that are event-triggered, ephemeral (may only last for one invocation)

Decentralized apps are a new type of software program designed to exist on the Internet in a way that is not controlled by any single entity. Where bitcoin is a decentralized value exchange, a decentralized application aims to achieve functionality beyond transactions that exchange value. Many types of decentralized apps are starting to emerge as blockchain technology continues to progress. More companies and individuals are seeing the potential for what can be achieved in decentralizing not just money but almost any type of computing imaginable.

Decentralized apps potentially represent the next generation of computing. In a completely decentralized world all things occur using peer-to-peer networks and the idea of centralized entities are non-existent. This distributed future is still being designed and built but the early stages of development are looking promising.

Blockstack domains are not registered on the traditional DNS run by an organized called ICANN. Instead they're registered on a blockchain in a fully decentralized way. This means that Blockstack domains are truly owned by their owners and cannot be taken away. All Blockstack domains have public keys by default (public keys are required to own the domains), unlike the traditional DNS where a small fraction of domains get the (optional) public key certificates.

Blockstack is designed around a "virtual chain" concept, where nodes only need to reach consensus on the shared "virtual chain" they're interested in. Virtual chains do not interact with one another, and a single blockchain can host many virtual chains. These virtual chains can live in any blockchain for which there exists a driver, and virtual chain clients only need to execute their virtual chain transactions (i.e. Blockstack only processes Blockstack virtual chain transactions).

Blockstack Core is the reference implementation of the Blockstack protocol described in our white paper. It consists of a couple of parts:

Virtualchain implementation: This is a python library that parses the underlying blockchain (Bitcoin) and builds the state of the Blockstack DNS.
Blockstack Core: Uses the Virtualchain to build the DNS state and comes to a consensus on that state in a peer network (Atlas).
Blockstack API: Indexes the data stored by Blockstack Core and makes it available in a performant way to applications.
The project is open-source and anyone can contribute! The major contributors are mostly employees of Blockstack PBC. You can see the full list of contributors here: https://github.com/blockstack/blockstack-core/graphs/contributors