| Formerly | Ohloh |
|---|---|
Type of site | Public directory offree and open-source software (FOSS) |
| Owner | Black Duck Software |
| Created by | Jason Allen and Scott Collison |
| URL | www |
| Commercial | yes |
| Launched | 1 January 2006; 19 years ago (2006-01-01) |
| Current status | Active |
Content license | Proprietary; interfaceApache License[1] |

Open Hub orBlack Duck Open Hub (formerlyOhloh)[2] is a website which provides aweb services suite andonline community platform that aims to index theopen-source software development community. It was founded by formerMicrosoft managers Jason Allen and Scott Collison in 2004 and joined by the developer Robin Luckey.[3][4] As of 15 January 2016[update], the site lists 669,601 open-source projects, 681,345 source control repositories, 3,848,524 contributors and 31,688,426,179 lines of code.[5]
In 2017,Black Duck Software (the company running the site) was acquired bySynopsys for $565 million,[6] however it was spun out as a separate company again in October 2024.[7]
Ohloh was founded by formerMicrosoft managers Jason Allen and Scott Collison in 2004, joined by developer Robin Luckey.[8][9] On 28 May 2009, Ohloh was acquired byGeeknet, owners of the popular open-source development platformSourceForge.[10] However, Geeknet sold Ohloh to the open-source analysis companyBlack Duck Software on 5 October 2010. Black Duck integrated Ohloh's functionality with their existing products to advance the site into a major resource for FOSS development.[11] On 18 July 2014, Ohloh became Black Duck Open Hub.[12] In late August 2014, the Black Duck Open Hub's Organizations feature moved out of Beta and into Version 1.0.[13]
By retrieving data fromrevision control repositories (such asCVS,SVN,Git,Bazaar, andMercurial), Black Duck Open Hub provides statistics about the longevity of projects, theirlicenses (including license conflict information), as well assoftware metrics such assource lines of code andcommit statistics. Thecodebase history informs about the amount of activity for each project.Software stacks (list of software applications used by Black Duck Open Hub's members) andtags are used to calculate the similarity between projects.
Global statistics per language measure the popularity of specificprogramming languages since the early 1990s.[14] Those global statistics across all projects in Black Duck Open Hub have also been used to identify those with the most extensive continuous revision control histories.[15]
Contributor statistics are also available, measuring open-source developers' experience as observable in code committed to revision control repositories.Social network features (kudos) have been introduced to allow users to rank open-source contributors. AKudoRank for each user and open-source contributor on a scale of 1 to 10 is automatically extracted from all kudos in the system.[16] The idea of measuring open-source developers' skills and productivity on the basis of commit statistics or mutual rating has received mixed reactions in technology blogs.[17][18] Contributor profiles may also contain a contributor suppliedemail address, and avatars loaded fromGravatar using that email address.
On 22 August 2007, a public beta of a web-serviceAPI was announced, exposing Black Duck Open Hub's data and reports to promote the development of third-party applications.[19]
On 18 January 2013, the team announced a new metric, the Project Activity Indicator (PAI). The PAI combines the number of contributors and the number of commits in an algorithm that weighs more recent activity more heavily than past activity. Activity is normalized so that all projects can be considered and weighed equally one against another; that activity assessment is scaled relatively to the number of project contributors and commits.[20]
On 14 January 2014, the team announced a new score, the Project Hotness Score. The PAI shows long-term activity and growth on FOSS projects, but its requirement that there be at least a year of data means that new projects can't be ranked. The Project Hotness Score looks at activity over the past few weeks and evaluates daily activity to identify those projects. By design, the Project Hotness Score is highly volatile.[21]
On 6 April 2016, the team announced Hub 3.0, which streamlinedcontinuous integration andDevOps processes through policy management and rapid scanning capabilities.[22]
In 2012, Black Duck Open Hub launched Open Hub Code Search, a free code search engine based on the predecessorKoders.[23] It could search over 21 billion lines of open-source code and filter by language, project or syntax, but was discontinued in 2016.[24]