A vertical slice, sometimes abbreviated to VS, is a type of milestone, benchmark, or deadline, with emphasis on demonstrating progress across all components of a project. It could be considered a project management buzzword, and may have originated in the games industry.
The term 'vertical slice' refers to a cross-sectional slice through the layers that form the structure of the software code base. It is mostly used in Scrum terminology where the work is planned in terms of features (or stories). For example as a very basic approach, a software project may consist of three layers (or components): Data access layer (bottom), Business logic layer (middle) and User interface Layer (top). In this very common approach, a vertical slice means a bit of every layer. Again as an example, a new feature request like 'showing x information on main screen' would contain these work bits:
- Work in the UI that will display the information
- Work in the business layer to transform the information
- Work in the database layer to store / fetch the information.
So a vertical slice can be defined as 'the sum of the work that has to be done in every layer that is involved in getting a specific feature working'. A vertical slice doesn't necessarily affect every component in the software. For example, if the solution contains a web service, it would live in the same 'floor' as the UI, and a feature like 'supporting login/logout in webservice' that involves only the web service doesn't require a change in the UI, but the business and database access layers.
Famous quotes containing the words vertical and/or slice:
“I tell you, hopeless grief is passionless;
That only men incredulous of despair,
Half-taught in anguish, through the midnight air
Beat upward to God’s throne in loud access
Of shrieking and reproach. Full desertness,
In souls as countries, lieth silent-bare
Under the blanching, vertical eye-glare
Of the absolute Heavens.”
—Elizabeth Barrett Browning (1806–1861)
“The places we have known do not only belong to the world of space in which we situate them for the sake of simplicity. They were but a thin slice between contiguous impression which formed our lives back then; the memory of a certain image is but the regret of a certain instant; and the houses, the roads, the avenues are fleeting, alas! as the years.”
—Marcel Proust (1871–1922)