In software development,

peer review Peer review is the evaluation of work by one or more people with similar competencies as the producers of the work (peers). It functions as a form of self-regulation by qualified members of a profession within the relevant field. Peer review ...

is a type of

software review A software review is "a process or meeting during which a software product is examined by a project personnel, managers, users, customers, user representatives, or other interested parties for comment or approval".IEEE Std . 1028-1997, "IEEE Standa ...

in which a work product (document, code, or other) is examined by author's colleagues, in order to evaluate the work product's technical content and quality.

Purpose

The purpose of a peer review is to provide "a disciplined engineering practice for detecting and correcting defects in software artifacts, and preventing their leakage into field operations" according to the

Capability Maturity Model The Capability Maturity Model (CMM) is a development model created in 1986 after a study of data collected from organizations that contracted with the U.S. Department of Defense, who funded the research. The term "maturity" relates to the degree of ...

. When performed as part of each

Software development process In software engineering, a software development process is a process of dividing software development work into smaller, parallel, or sequential steps or sub-processes to improve design, product management. It is also known as a software devel ...

activity, peer reviews identify problems that can be fixed early in the lifecycle. That is to say, a peer review that identifies a requirements problem during the

Requirements analysis In systems engineering and software engineering, requirements analysis focuses on the tasks that determine the needs or conditions to meet the new or altered product or project, taking account of the possibly conflicting requirements of the ...

activity is cheaper and easier to fix than during the

Software architecture Software architecture is the fundamental structure of a software system and the discipline of creating such structures and systems. Each structure comprises software elements, relations among them, and properties of both elements and relations. ...

Software testing Software testing is the act of examining the artifacts and the behavior of the software under test by validation and verification. Software testing can also provide an objective, independent view of the software to allow the business to apprecia ...

activities. The National Software Quality Experiment, evaluating the effectiveness of peer reviews, finds, "a favorable return on investment for software inspections; savings exceeds costs by 4 to 1". To state it another way, it is four times more costly, on average, to identify and fix a software problem later.

Distinction from other types of software review

Peer reviews are distinct from management reviews, which are conducted by management representatives rather than by colleagues, and for management and control purposes rather than for technical evaluation. They are also distinct from

software audit review A software audit review, or software audit, is a type of software review in which one or more auditors who are not members of the software development organization conduct "An independent examination of a software product, software process, or set ...

s, which are conducted by personnel external to the project, to evaluate compliance with specifications, standards, contractual agreements, or other criteria.

Review processes

Peer review processes exist across a spectrum of formality, with relatively unstructured activities such as "buddy checking" towards one end of the spectrum, and more Informal approaches such as walkthroughs,

technical peer review In engineering, technical peer review is a type of engineering review. Technical peer reviews are a well defined review process for finding and fixing defects, conducted by a team of peers with assigned roles. Technical peer reviews are carried out ...

s, and

software inspection Inspection in software engineering, refers to peer review of any work product by trained individuals who look for defects using a well defined process. An inspection might also be referred to as a Fagan inspection after Michael Fagan, the creato ...

s, at the other. The

IEEE The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operation ...

defines formal structures, roles, and processes for each of the last three. Management representatives are typically not involved in the conduct of a peer review except when included because of specific technical expertise or when the work product under review is a management-level document. This is especially true of line managers of other participants in the review. Processes for formal peer reviews, such as

s, define specific roles for each participant, quantify stages with entry/exit criteria, capture

software metrics In software engineering and development, a software metric is a standard of measure of a degree to which a software system or process possesses some property. Even if a metric is not a measurement (metrics are functions, while measurements are t ...

on the peer review process.

"Open source" reviews

In the free / open source community, something like peer review has taken place in the engineering and evaluation of

computer software Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work. At the lowest programming level, executable code consists ...

. In this context, the rationale for peer review has its equivalent in

Linus's law In software development, Linus's law is the assertion that "given enough eyeballs, all bugs are shallow". The law was formulated by Eric S. Raymond in his essay and book '' The Cathedral and the Bazaar'' (1999), and was named in honor of Linu ...

, often phrased: "Given enough eyeballs, all bugs are shallow", meaning "If there are enough reviewers, all problems are easy to solve."

Eric S. Raymond Eric Steven Raymond (born December 4, 1957), often referred to as ESR, is an American software developer, open-source software advocate, and author of the 1997 essay and 1999 book ''The Cathedral and the Bazaar''. He wrote a guidebook for the ...

has written influentially about peer review in

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 invol ...

.{{cite document, author=Eric S. Raymond, title=The Cathedral and the Bazaar, title-link=The Cathedral and the Bazaar, author-link=Eric S. Raymond

References

Software review Peer review