Inner Source


Inner Source is the use of open source software development best practices and the establishment of an open source-like culture within organizations. The organization may still develop proprietary software, but internally opens up its development. The term was coined by Tim O'Reilly in 2000.

Motivation

is recognized to be capable of delivering high quality software. Furthermore, the open collaboration in open source enables collaboration even between competitors.
Consequently, software developing organizations want to benefit from its outcomes, but also from the development practices exercised and established in the open source world.

Used open source practices

Besides several practices established in foundations such as Apache Software Foundation, Linux Foundation, and Eclipse Foundation, inner source and open source projects require open collaboration, open communication, and a proper quality assurance.

Open collaboration

All required development artifacts have to be accessible for all employees of a company leveraging inner source. Central software forges are an essential tool for implementing open collaboration.
Based on the principles of open collaboration every contributor who is willing to help an inner source project is typically welcome. Contributions to inner source projects are typically judged meritocratically based on the value they bring to the project. Meritocracy can also be enabled by open communication as decisions are discussed publicly. Although an organization does not necessarily become completely self-organizing to adopt inner source, inner source allows individuals, organizational units, and project communities a higher degree of self-organization.

Open communication

Inner source projects and programs rely on open communication to make all communication openly accessible for all employees. Open communication is communication that is public, written, archived, and complete. The goal is to allow any individual or party that has stake or interest in an inner source project to participate in the communication. As open communication discussions are archived, a detailed documentation of the software is passively gathered that allows one to go back and revisit historic discussions and decisions.

Quality assurance through separation of contribution from integration

A dedicated code review and the separation of contributors and committers assures the quality of an open source project, and, therefore, also for an inner source project.

Benefits

Beyond the quality attributes of open source software the following benefits are reported:
; More efficient and effective development
; Overcoming organizational unit boundaries
; More successful reuse
; Better software product
; More flexible utilization of developers
; Enhanced knowledge management
; Higher employee motivation

Prevalence

Among others the following companies are known for adopting inner source:
Inner source can be a promising approach for large organizations that develop software. However, it may not be appropriate in all settings. The following nine factors, grouped in three categories, can be consulted to gauge the extent to which inner source may be appropriate.

Product factors