Draft:Holochain

Holochain is an open source framework for developing and deploying distributed applications. Its purpose is to enable the kinds of activities people do on the Internet every day (wikis, blogs, social networks, marketplaces, etc.) without using centralized servers. Instead, Holochain applications are run on the users’ devices. It has been proposed as an alternative technology to blockchain-based systems and centralized platforms.

Although the Holochain project has been in development for more than 10 years, the first Beta release happened in January 2023. Therefore, it has not yet been tested as extensively as blockchains in real-world environments.

Co-founders of Holochain are Arthur Brock and Eric Harris-Braun.

Technical background
Holochain is an open-source framework for developing distributed applications, utilizing a novel implementation of distributed hash tables (DHT) called RRDHT, inspired by BitTorrent, along with concepts similar to Git for data management, and cryptographic signatures for ensuring data integrity. The main difference between Holochain and other distributed ledger technologies (DLTs) is that Holochain is agent-centric while other DLTs are data-centric. It has been classified as a type of private and permissionless DLT for building decentralized applications.

An agent-centric approach to applications means that each agent stores only relevant data, and unlike Bitcoin and other blockchain systems, there is no singular centralized database to be maintained. Where blockchains operate with a global consensus model, often leading to scalability issues, Holochain implements an agent-centric model. This means that rather than maintaining a single, unified ledger of all transactions or interactions, each user on Holochain has their own individual chain of data, or "source chain", that represents their history of actions. The personal chain interacts with a DHT that provides a means for the larger network to verify the data by peers that are randomly selected. This difference makes it more efficient than blockchain, as demonstrated by its ability to run over 50 full nodes on a single Raspberry Pi. In the scientific literature, there are performance analyses conducted to compare the efficiency, resource usage, privacy, and security levels of Holochain-based solutions and blockchain-based solutions. Holochain has been compared to proof-of-work and proof-of-stake blockchains in terms of its environmental impact.

Projects using Holochain
Here are some Holochain-based projects being developed by independent groups:

hREA (open beta testing)
hREA (Holochain Resource-Event-Agent) is an implementation of the Valueflows specification, providing a scalable and distributed framework for economic network coordination. It allows for transparent and trusted resource and information flows between decentralized agents in various ecosystems, enabling organizations and businesses to track and trace value flows in both conventional and alternative economies.

HummHive (open beta testing)
HummHive is a platform that allows people to create, store, and share content, like stories and media, securely and privately. It gives users the freedom to customize their experience and manage their audience without relying on centralized servers or being subjected to tracking and advertising.

MewsFeed (beta release)
MewsFeed is a microblogging platform, alternative to Twitter or Mastodon.

AD4M (alpha testing)
AD4M is a framework for distributed social spaces, enabling seamless interoperability among various apps. With its core concepts of agents, languages, and perspectives, AD4M facilitates collaborative data sharing and group interactions, while remaining technology-agnostic, allowing developers to integrate with various technologies like Holochain, blockchains, and centralized APIs.

Flux (alpha testing)
Flux is a distributed social platform that allows users to create private communities and organize communication channels. Built on the AD4M framework, it aims to provide a customizable user interface and feature set, with plans for future features such as distributed governance and Web3 integrations.

Internet of Energy Network (in development)
Internet of Energy Network (IOEN) is an open-source project that aims to promote clean energy by enabling community and local energy system balancing and coordination. It employs a dual-layered solution with IOENFuel for local transactions and the IOEN Token for global value transfer.

Kizuna (in development)
Kizuna is an open-source, non-profit messaging app built on Holochain, focused on user privacy and data control. It offers encrypted communication and self-destructing messages, with an emphasis on censorship resistance. Kizuna is ad-free and claims to be independent of corporate interests.

Neighbourhoods (in development)
Neighbourhoods focuses on user-centric social apps and collaboration tools. It allows users to customize group interactions and store records on their devices for peer-to-peer communication. The project features an embedded marketplace for developers and uses its native currency, $NHT, to support the code commons.

Sustafy (in development)
Sustafy is a supply chain transparency app that collects real-time origin data for handmade craft makers, helping them comply with the EU's Digital Product Passport (DPP) legislation. By supporting the UN Sustainable Development Goals, the project aims to provide artisans and small-scale farmers with improved access to financial tools, markets, and cooperatives.

Trust Graph (in development)
Trust Graph is an open protocol and toolkit for building and reading distributed trust graphs, designed to share trust, ratings, and attestation information across decentralized apps and platforms.

Hylo (in development)
Hylo is a platform for managing and organizing communities, providing tools for communication, collaboration, and membership management. Suitable for various group sizes, it supports conversation organization, file sharing, and networking among affiliated communities.

Potential Limitations
Despite its potential advantages and innovative approach, Holochain also faces several challenges and limitations. This section outlines some of these issues, including technical limitations, adoption barriers, and competition from other technologies.


 * 1) Technical limitations: As a relatively new technology, Holochain's performance and security have not yet been tested as extensively as those of established blockchain platforms.  While early studies have shown promising results, it remains to be seen how the framework will fare under real-world conditions, including potential attacks or large-scale usage.
 * 2) Adoption barriers: Like any emerging technology, Holochain faces challenges in terms of adoption and integration with existing systems. The success of the framework will depend on its ability to attract developers, businesses, and users, as well as its compatibility with existing infrastructure and regulatory environments. Additionally, the agent-centric nature of Holochain may require a paradigm shift in how developers and organizations approach distributed applications, potentially slowing adoption.
 * 3) Competing technologies: Holochain is not the only technology seeking to provide a decentralized alternative to the centralized web. Activitypub is a social networking protocol that gained increased adoption in 2022 with the growth of the Twitter-alternative, Mastodon. Tim Berners-Lee, inventor of the World Wide Web, has a new project called Solid, which aims to give users more control over their personal data and lets them choose where the data goes. Other projects, such as Ethereum 2.0, Polkadot, and IOTA also aim to provide scalable, efficient, and secure solutions for decentralized applications. The success of Holochain will depend on its ability to differentiate itself and offer unique advantages over these and other competing platforms.
 * 4) Regulatory concerns: While Holochain has been suggested as a potential solution for compliance with regulations like the European Union's "right to be forgotten" ruling, it may still face regulatory hurdles in other areas. As governments and regulatory bodies continue to develop and enforce rules surrounding the use of distributed ledger technologies, the impact of these regulations on Holochain's growth and adoption remains uncertain.