GitHub

GitHub, Inc. is a provider of Internet hosting for software development and version control using Git. It offers the distributed version control and source code management (SCM) functionality of Git, plus its own features. It provides access control and several collaboration features such as bug tracking, feature requests, task management, continuous integration and wikis for every project. Headquartered in California, it has been a subsidiary of Microsoft since 2018.
GitHub offers its basic services free of charge. Its more advanced professional and enterprise services are commercial. Free GitHub accounts are commonly used to host open-source projects. As of January 2019, GitHub offers unlimited private repositories to all plans, including free accounts, but allowed only up to three collaborators per repository for free. Starting from April 15, 2020, the free plan allows unlimited collaborators, but restricts private repositories to 2,000 minutes of GitHub Actions per month. As of January 2020, GitHub reports having over 40 million users and more than 190 million repositories (including at least 28 million public repositories), making it the largest host of source code in the world.
History.
GitHub.com.
Development of the GitHub.com platform began on October 19, 2007. The site was launched in April 2008 by Tom Preston-Werner, Chris Wanstrath, P. J. Hyett and Scott Chacon after it had been made available for a few months prior as a beta release.
Organizational structure.
GitHub, Inc. was originally a flat organization with no middle managers; in other words, "everyone is a manager" (self-management). Employees could choose to work on projects that interested them (open allocation), but salaries were set by the chief executive.
In 2014, GitHub, Inc. introduced a layer of middle management.
Finance.
GitHub.com was a bootstrapped start-up business, which in its first years provided enough revenue to be funded solely by its three founders and start taking on employees. In July 2012, four years after the company was founded, Andreessen Horowitz invested $100 million in venture capital. In July 2015 GitHub raised another $250 million of venture capital in a series B round. Investors were Sequoia Capital, Andreessen Horowitz, Thrive Capital and other venture capital funds. As of August 2016, GitHub was making $140 million in Annual Recurring Revenue.
The GitHub service was developed by Chris Wanstrath, P. J. Hyett, Tom Preston-Werner and Scott Chacon using Ruby on Rails, and started in February 2008. The company, GitHub, Inc., has existed since 2007 and is located in San Francisco.
On February 24, 2009, GitHub announced that within the first year of being online, GitHub had accumulated over 46,000 public repositories, 17,000 of which were formed in the previous month. At that time, about 6,200 repositories had been forked at least once and 4,600 had been merged.
That same year, the site was harnessed by over 100,000 users, according to Github, and had grown to host 90,000 unique public repositories, 12,000 having been forked at least once, for a total of 135,000 repositories.
In 2010, GitHub was hosting 1 million repositories. A year later, this number doubled. ReadWriteWeb reported that GitHub had surpassed SourceForge and Google Code in total number of commits for the period of January to May 2011. On January 16, 2013, GitHub passed the 3 million users mark and was then hosting more than 5 million repositories. By the end of the year, the number of repositories were twice as much, reaching 10 million repositories.
In 2012, GitHub raised $100 million in funding from Andreessen Horowitz with $750 million valuation. On July 29, 2015, GitHub stated it had raised $250 million in funding in a round led by Sequoia Capital. Other investors of that round included Andreessen Horowitz, Thrive Capital, and IVP (Institutional Venture Partners). The round valued the company at approximately $2 billion.
In 2015, GitHub opened an office in Japan, its first outside of the U.S. In 2016, GitHub was ranked No. 14 on the "Forbes" Cloud 100 list. It has not been featured on the 2018, 2019 and 2020 lists.
On February 28, 2018, GitHub fell victim to the third largest distributed denial-of-service (DDoS) attack in history, with incoming traffic reaching a peak of about 1.35 terabits per second.
On June 19, 2018, GitHub expanded its GitHub Education by offering free education bundles to all schools.
Acquisition by Microsoft.
From 2012, Microsoft became a significant user of GitHub, using it to host open-source projects and development tools such as .NET Core, Chakra Core, MSBuild, PowerShell, PowerToys, Visual Studio Code, Windows Calculator, Windows Terminal and the bulk of its product documentation (now to be found on Microsoft Docs).
On June 4, 2018, Microsoft announced its intent to acquire GitHub for US$7.5 billion. The deal closed on October 26, 2018. GitHub continued to operate independently as a community, platform and business. Under Microsoft, the service was led by Xamarin's Nat Friedman, reporting to Scott Guthrie, executive vice president of Microsoft Cloud and AI. GitHub's CEO, Chris Wanstrath, was retained as a "technical fellow", also reporting to Guthrie.
There have been concerns from developers Kyle Simpson, JavaScript trainer and author, and Rafael Laguna, CEO at Open-Xchange over Microsoft's purchase, citing uneasiness over Microsoft's handling of previous acquisitions, such as Nokia's mobile business or Skype.
This acquisition was in line with Microsoft's business strategy under CEO Satya Nadella, which has seen a larger focus on the cloud computing services, alongside development of and contributions to open-source software. "Harvard Business Review" argued that Microsoft was intending to acquire GitHub to get access to its user base, so it can be used as a loss leader to encourage use of its other development products and services.
Concerns over the sale bolstered interest in competitors: Bitbucket (owned by Atlassian), GitLab (a commercial open source product that also runs a hosted service version) and SourceForge (owned by BIZX, LLC) reported that they had seen spikes in new users intending to migrate projects from GitHub to their respective services.
In September 2019, GitHub acquired Semmle, a code analysis tool. In February 2020, GitHub launched in India under the name GitHub India Private Limited. In March 2020, GitHub announced that they were acquiring npm, a JavaScript packaging vendor, for an undisclosed sum of money. The deal was closed on 15 April 2020.
In early July 2020, the GitHub Archive Program was established, to archive its open source code in perpetuity.
Mascot.
GitHub's mascot is an anthropomorphized "octocat" with five octopus-like arms. The character was created by graphic designer Simon Oxley as clip art to sell on iStock, a website that enables designers to market royalty-free digital images. GitHub became interested in Oxley's work after Twitter selected a bird that he designed for their own logo. The illustration GitHub chose was a character that Oxley had named Octopuss. Since GitHub wanted Octopuss for their logo (a use that the iStock license disallows), they negotiated with Oxley to buy exclusive rights to the image.
GitHub renamed Octopuss to Octocat, and trademarked the character along with the new name. Later, GitHub hired illustrator Cameron McEfee to adapt Octocat for different purposes on the website and promotional materials; McEfee and various GitHub users have since created hundreds of variations of the character, which are available on The Octodex.
Services.
Projects on GitHub.com can be accessed and managed using the standard Git command-line interface; all standard Git commands work with it. GitHub.com also allows users to browse public repositories on the site. Multiple desktop clients and Git plugins are also available. The site provides social networking-like functions such as feeds, followers, wikis (using wiki software called Gollum) and a social network graph to display how developers work on their versions ("forks") of a repository and what fork (and branch within that fork) is newest.
Anyone can browse and download public repositories but only registered users can contribute content to repositories. With a registered user account, users are able to have discussions, manage repositories, submit contributions to others' repositories, and review changes to code. GitHub.com began offering unlimited private repositories at no cost in January 2019 (limited to three contributors per project). Previously, only public repositories were free. On April 14, 2020, GitHub made "all of the core GitHub features" free for everyone, including "private repositories with unlimited collaborators".
The fundamental software that underpins GitHub is Git itself, written by Linus Torvalds, creator of Linux. The additional software that provides the GitHub user interface was written using Ruby on Rails and Erlang by GitHub, Inc. developers Wanstrath, Hyett, and Preston-Werner.
Scope.
The main purpose of GitHub.com is to facilitate the version control and issue tracking aspects of software development. Labels, milestones, responsibility assignment, and a search engine are available for issue tracking. For version control, Git (and by extension GitHub.com) allows pull requests to propose changes to the source code. Users with the ability to review the proposed changes can see a diff of the requested changes and approve them. In Git terminology, this action is called "committing" and one instance of it is a "commit". A history of all commits are kept and can be viewed at a later time.
In addition, GitHub supports the following formats and features:
GitHub's Terms of Service do not require public software projects hosted on GitHub to meet the Open Source Definition. The terms of service state, "By setting your repositories to be viewed publicly, you agree to allow others to view and fork your repositories."
GitHub Enterprise.
GitHub Enterprise is a self-managed version of GitHub.com with similar functionality. It can be run on an organization's own hardware or on a cloud provider, and it has been available since November 2011. In November 2020, source code for GitHub Enterprise Server was leaked online in apparent protest against DMCA takedown of YouTube-dl. According to GitHub, the source code came from GitHub accidentally sharing the code with Enterprise customers themselves, not from an attack on GitHub servers.
GitHub Pages.
GitHub Pages is a static web hosting service offered by GitHub since 2008 to GitHub users for hosting user blogs, project documentation, or even whole books created as a page.
All GitHub Pages content is stored in a Git repository, either as files served to visitors verbatim or in Markdown format. GitHub is seamlessly integrated with Jekyll static web site and blog generator and GitHub continuous integration pipelines. Each time the content source is updated, Jekyll regenerates the website and automatically serves it via GitHub Pages infrastructure.
As with the rest of GitHub, it includes both free and paid tiers of service, instead of being supported by web advertising. Web sites generated through this service are hosted either as subdomains of the github.io domain, or as custom domains bought through a third-party domain name registrar. When custom domain is set on a GitHub Pages repo a Let's Encrypt certificate for it is generated automatically. Once the certificate has been generated Enforce HTTPS can be set for the repository's website to transparently redirect all HTTP requests to HTTPS.
Gist.
GitHub also operates other services: a pastebin-style site called Gist that is for hosting code snippets (GitHub proper is for hosting larger projects).
Tom Preston-Werner presented the then-new Gist feature at a punk rock Ruby conference in 2008. Gist builds on the traditional simple concept of a pastebin by adding version control for code snippets, easy forking, and TLS encryption for private pastes. Because each "gist" has its own Git repository, multiple code snippets can be contained in a single paste and they can be pushed and pulled using Git. Further, forked code can be pushed back to the original author in the form of a patch, so gists (pastes) can become more like mini-projects.
Before February 18, 2018, unregistered users were able to upload text to the site. Since then, uploading gists has been deactivated for unregistered users with the aim to mitigate spamming.
Education program.
GitHub launched a new program called the GitHub Student Developer Pack to give students free access to popular development tools and services. GitHub partnered with Bitnami, Crowdflower, DigitalOcean, DNSimple, HackHands, Namecheap, Orchestrate, Screenhero, SendGrid, Stripe, Travis CI and Unreal Engine to launch the program.
In 2016 GitHub announced the launch of the GitHub Campus Experts program to train and encourage students to grow technology communities at their universities. The Campus Experts program is open to university students of 18 years and older across the world. GitHub Campus Experts are one of the primary ways that GitHub funds student oriented events and communities, Campus Experts are given access to training, funding, and additional resources to run events and grow their communities. To become a Campus Expert applicants must complete an online training course consisting of multiple modules designed to grow community leadership skills.
GitHub Marketplace service.
GitHub also provides some software as a service integrations for adding extra features to projects. Those services include:
GitHub Sponsors.
GitHub Sponsors allows users to make monthly money donations to projects hosted on GitHub. The public beta was announced on May 23, 2019 and currently the project accepts wait list registrations. The Verge said that GitHub Sponsors "works exactly like Patreon" because "developers can offer various funding tiers that come with different perks, and they’ll receive recurring payments from supporters who want to access them and encourage their work" except with "zero fees to use the program". Furthermore, GitHub offer incentives for early adopters during the first year: it pledges to cover payment processing costs, and match sponsorship payments up to $5,000 per developer. Furthermore, users still can use other similar services like Patreon and Open Collective and link to their own websites.
GitHub Archive Program.
In July 2020, GitHub stored a February archive of the site in an abandoned mountain mine in Svalbard, Norway, part of the Arctic World Archive and not far from the Svalbard Global Seed Vault. The archive contained the code of all active public repositories, as well as that of dormant, but significant public repositories. The 21TB of data was stored on piqlFilm archival film reels as matrix (2D) barcode (Boxing barcode), and is expected to last 500–1,000 years.
The GitHub Archive Program is also working with partners on Project Silica, in an attempt to store all public repositories for 10,000 years. It aims to write archives into the molecular structure of quartz glass platters, using a high-precision laser that pulses a quadrillion (1,000,000,000,000,000) times per second.
Controversies.
Harassment allegations.
In March 2014, GitHub programmer Julie Ann Horvath alleged that founder and CEO Tom Preston-Werner and his wife Theresa engaged in a pattern of harassment against her that led to her leaving the company. In April 2014, GitHub released a statement denying Horvath's allegations. However, following an internal investigation, GitHub confirmed the claims. GitHub's CEO Chris Wanstrath wrote on the company blog, "The investigation found Tom Preston-Werner in his capacity as GitHub's CEO acted inappropriately, including confrontational conduct, disregard of workplace complaints, insensitivity to the impact of his spouse's presence in the workplace, and failure to enforce an agreement that his spouse should not work in the office." Preston-Werner subsequently resigned from the company. The firm then announced it would implement new initiatives and trainings "to make sure employee concerns and conflicts are taken seriously and dealt with appropriately."
Sanctions.
On July 25, 2019, a developer based in Iran wrote on Medium about how GitHub blocked his private repositories, and prohibited access to GitHub Pages. Soon after, GitHub confirmed that it was now blocking developers in Iran, Crimea, Cuba, North Korea, and Syria from accessing private repositories. However, GitHub reopened access to GitHub Pages days later, for public repositories regardless of location. It was also revealed that using GitHub while visiting sanctioned countries could result in similar action occurring on a user's account. GitHub responded to complaints and the media through a spokesperson, saying:
GitHub is subject to US trade control laws, and is committed to full compliance with applicable law. At the same time, GitHub's vision is to be the global platform for developer collaboration, no matter where developers reside. As a result, we take seriously our responsibility to examine government mandates thoroughly to be certain that users and customers are not impacted beyond what is required by law. This includes keeping public repositories services, including those for open source projects, available and accessible to support personal communications involving developers in sanctioned regions.
Developers who feel that they should not have restrictions can appeal for the removal of said restrictions, including those who only travel to, and do not reside in, those countries. GitHub has forbidden the use of VPNs and IP proxies to access the site from sanctioned countries, as purchase history and IP addresses are how they flag users, among other sources.
Censorship.
On December 3, 2014, Russia blacklisted GitHub.com because GitHub initially refused to take down user-posted suicide manuals. After a day, Russia withdrew its block, and GitHub began blocking too specific content and pages in Russia. On December 31, 2014, India blocked GitHub.com along with 31 other websites over pro-ISIS content posted by users; the block was lifted three days later. On October 8, 2016, Turkey blocked GitHub to prevent email leakage of a hacked account belonging to the country's energy minister.
On March 26, 2015, a large-scale DDoS attack was launched against GitHub.com that lasted for just under five days. The attack, which appeared to originate from China, primarily targeted GitHub-hosted user content describing methods of circumventing Internet censorship.
On April 19, 2020, Chinese police detained Chen Mei and Cai Wei (volunteers for Terminus 2049, a project hosted on GitHub), and accused them of "picking quarrels and provoking trouble". Cai and Chen archived news articles, interviews, and other materials published on Chinese media outlets and social media platforms that have been removed by censors in China.
ICE contract.
GitHub has a $200,000 contract with U.S. Immigration and Customs Enforcement (ICE) for the use of their on-site product GitHub Enterprise Server. This contract was renewed in 2019, despite internal opposition from many GitHub employees. In an email sent to employees, later posted to the GitHub blog on October 9, 2019, CEO Nat Friedman stated "The revenue from the purchase is less than $200,000 and not financially material for our company." He announced that GitHub had pledged to donate $500,000 to "nonprofit groups supporting immigrant communities targeted by the current administration." In response at least 150 GitHub employees signed an open letter re-stating their opposition to the contract, and denouncing alleged human rights abuses by ICE. As of November 13, 2019, five workers had resigned over the contract.
The ICE contract dispute came into focus again in June 2020 due to the company's decision to abandon "master/slave" branch terminology, spurred by the George Floyd protests and Black Lives Matter movement. Detractors of GitHub describe the branch renaming to be a form of performative activism and have urged GitHub to cancel their ICE contract instead. An open letter from members of the open source community was shared on GitHub in December 2019, demanding that the company drop their contract with ICE and provide more transparency into how they conduct business and partnerships. The letter has been signed by over 700 people.
Capitol riot comments and employee firing.
In January 2021, GitHub fired one of its employees after he expressed concern for colleagues as a violent mob stormed the U.S. Capitol, calling some of the rioters "Nazis". After an investigation, GitHub's COO said there were "significant errors of judgment and procedure" with the company's decision to fire the employee. As a result of the investigation, Github reached out to the employee and the company's head of human resources resigned.
Prominent users.
Some prominent open source organizations and projects use GitHub as a primary place for collaboration, including: