In FOSS development communities, a forge is a web-based collaborative software platform for both developing and sharing computer applications. The term ''forge'' refers to a common prefix or suffix adopted by various platforms created after the example of SourceForge. This usage of the word stems from the metalworking forge, used for shaping metal parts. For software developers it is an online service to host the tools they need to communicate with their coworkers. The source code itself is stored in a

revision control In software engineering, version control (also known as revision control, source control, or source code management) is a class of systems responsible for managing changes to computer programs, documents, large web sites, or other collections o ...

system and linked to a wide range of services such as a bug database, continuous integration, etc. When a FOSS development community forks, it duplicates the content of the forge and is then able to modify it without asking permission. A community may rely on services scattered on multiple forges: they are not necessarily hosted under the same domain. For instance it is not uncommon for discussions to be hosted on

Discourse Discourse is a generalization of the notion of a conversation to any form of communication. Discourse is a major topic in social theory, with work spanning fields such as sociology, anthropology, continental philosophy, and discourse analysis. ...

while the source code is hosted on Gitea. For users, a forge is a repository of computer applications, a place where bugs can be reported, a channel to be informed of security issues, etc. Software forges became popular in 2001, and have proven successful as a

software development Software development is the process of conceiving, specifying, designing, programming, documenting, testing, and bug fixing involved in creating and maintaining applications, frameworks, or other software components. Software development inv ...

environment for millions of software projects.

Technology

Two different kinds of concepts are commonly referred to by the term ''forge'': * a ''service'' offered on a Web platform to host software development projects; * an integrated set of ''software'' elements which produce such platforms, ready for deployment. All these platforms provide similar tools helpful to software developers working in the hosted projects: * source code management systems * mailing-lists or

forum Forum or The Forum (plural forums or fora) may refer to: Common uses *Forum (legal), designated space for public expression in the United States *Forum (Roman), open public space within a Roman city **Roman Forum, most famous example *Internet ...

s * wikis * download services * bug tracking system Some provide other features as well: * code review

Interoperability

API and webhooks

In addition to the web

user interface In the industrial design field of human–computer interaction, a user interface (UI) is the space where interactions between humans and machines occur. The goal of this interaction is to allow effective operation and control of the machine f ...

, it is common for a forge to provide a REST API with the a documentation (

GitHub GitHub, Inc. () is an Internet hosting service for software development and version control using Git. It provides the distributed version control of Git plus access control, bug tracking, software feature requests, task management, co ...

, GitLab, Gitea, etc.) to enable interoperability with other products. Forge users can also install webhooks to notify a third party online service when an event happens on their software project (for instance the webhook can be called when a new issue is created).

Federation

Federation A federation (also known as a federal state) is a political entity characterized by a union of partially self-governing provinces, states, or other regions under a central federal government (federalism). In a federation, the self-govern ...

and the associated protocol ActivityPub (introduced in 2018) allows forges to communicate with each other about their activities (for instance when issues are created or a commit is pushed). Although native federation support is sometime discussed or in progress it is not yet available. Third party projects emerged to bridge the gap such as a plugin for the pagure forge or a proxy supporting ActivityPub and translating it to REST API calls to the designated forge.

Authentication

There is no SSO that applications and users could rely on to authenticate with all forges. Instead it is common for a forge to support a number of authentication providers: if a user already has an account they can use it to authenticate on the forge and do not need to create a new account (for instance GitLab supports

OAuth2 OAuth (short for "Open Authorization") is an open standard for access Delegation (computer security), delegation, commonly used as a way for internet users to grant websites or applications access to their information on other websites but witho ...

providers such as

). Some forges can act as an authentication provider (for instance Gitea is an OAuth2 provider as well as GitLab).

Integration

To improve the user and the system administrator experience when using multiple online services, some forges are integrated with popular third-party software and services such as online chat (for instance

mattermost Mattermost is an open-source, self-hostable online chat service with file sharing, search, and integrations. It is designed as an internal chat for organisations and companies, and mostly markets itself as an open-source alternative to Slack a ...

has a plugin for GitHub and is natively support by GitLab).

Examples

Free software

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* FusionForge * Gitea * GitBucket (GitHub compatible) * Joinup (Drupal-based) * Kallithea * Launchpad Suite * Phabricator * Redmine * SourceHut * Trac * Tuleap

Freemium software

* GitLab * GForge Advanced Server

Free online services

* Joinup collaboration platform * Launchpad * OSDN (Open Source Development Network) * SourceForge * GNU Savannah
sourcehut
(while in alpha)

Freemium online services

* GitLab *

* Bitbucket

Discontinued software

* Savane (software) * GForge Community Edition (last release April 23, 2010), not to be confused with the proprietary GForge first released October 1, 2018.

Discontinued online services

BerliOS BerliOS (short for "Berlin Open Source") is a project founded by the Fraunhofer Institute for Open Communication Systems (FOKUS), Berlin, to coordinate the different interest groups in the field of open source software (OSS) and to assume a neu ...

(It was disbanded in 2014, some projects have been moved to Joinup collaboration platform.) * CodePlex (Shut down on December 15, 2017) *

Gitorious Gitorious was a free and open source web application for hosting collaborative free and open-source Free and open-source software (FOSS) is a term used to refer to groups of software consisting of both free software and open-source software ...

(deprecated, superseded by GitLab) *

Gna.org Gna! was a centralized location where software developers could develop, distribute and maintain free software. The service was shut down in 2017 after 13 years in service for dozens of software projects and millions of downloads served. Since Ma ...

* Google Code * Open Source Assistive Technology Software (OATS) * Project Kenai (created by Sun Microsystems but shut down by Oracle) * Tigris.org (Shut down on July 1, 2020)

References

Project hosting websites {{programming-software-stub