Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Twelve-Factor App methodology
open-in-new
<h2 id="history">History</h2> <p>The methodology was drafted by developers at <a href="/facts/Heroku/yKTy97oV">Heroku</a>, a <a href="/facts/Platform_as_a_service/EDX8mcw4">platform-as-a-service</a> company, and was first presented by Adam Wiggins circa 2011.<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a> </p> <h2 id="the-twelve-factors">The Twelve Factors</h2> The Twelve Factors<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a><a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a><table><tbody><tr><th>#</th><th>Factor</th><th>Description</th></tr><tr><td>I</td><td>Codebase</td><td>There should be exactly one codebase for a deployed service with the codebase being used for many deployments.</td></tr><tr><td>II</td><td>Dependencies</td><td>All dependencies should be declared, with no implicit reliance on system tools or libraries.</td></tr><tr><td>III</td><td>Config</td><td>Configuration that varies between deployments should be stored in the environment.</td></tr><tr><td>IV</td><td>Backing services</td><td>All backing services are treated as attached resources and attached and detached by the execution environment.</td></tr><tr><td>V</td><td>Build, release, run</td><td>The delivery pipeline should strictly consist of build, release, run.</td></tr><tr><td>VI</td><td>Processes</td><td>Applications should be deployed as one or more stateless processes with persisted data stored on a backing service.</td></tr><tr><td>VII</td><td><a href="/facts/Port_(computer_networking)/ygoHVKNC">Port</a> binding</td><td>Self-contained services should make themselves available to other services by specified ports.</td></tr><tr><td>VIII</td><td><a href="/facts/Concurrent_computing/yVzQBPr9">Concurrency</a></td><td>Concurrency is advocated by scaling individual processes.</td></tr><tr><td>IX</td><td>Disposability</td><td>Fast startup and shutdown are advocated for a more robust and resilient system.</td></tr><tr><td>X</td><td>Dev/Prod parity</td><td>All environments should be as similar as possible.</td></tr><tr><td>XI</td><td>Logs</td><td>Applications should produce logs as event streams and leave the execution environment to aggregate.</td></tr><tr><td>XII</td><td>Admin Processes</td><td>Any needed admin tasks should be kept in source control and packaged with the application.</td></tr></tbody></table> <h2 id="criticism-and-adaptation">Criticism and adaptation</h2> <p>An <a href="/facts/Nginx/AlTYUuTp">Nginx</a> architect argued that the relevance of the Twelve-Factor app concept is somewhat specific to Heroku, while introducing their own (Nginx's) proposed architecture for microservices.<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a> The twelve factors are however cited as a baseline from which to adapt or extend.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a> </p> <h2 id="external-links">External links</h2> <ul><li><a href="https://12factor.net/">12factor Website</a></li> <li><a href="https://12factor.net/12factor.epub">The Twelve-Factor App epub book by Adam Wiggins</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>Hofmann, Michael; Schnabel, Erin; Stanley, Katherine (13 March 2017). Microservices Best Practices for Java. IBM Redbooks. pp. 2–3. ISBN 9780738442273. <a href="9780738442273" target="_blank">9780738442273</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Hofmann, Michael; Schnabel, Erin; Stanley, Katherine (13 March 2017). Microservices Best Practices for Java. IBM Redbooks. pp. 2–3. ISBN 9780738442273. <a href="9780738442273" target="_blank">9780738442273</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Hofmann, Michael; Schnabel, Erin; Stanley, Katherine (13 March 2017). Microservices Best Practices for Java. IBM Redbooks. pp. 2–3. ISBN 9780738442273. <a href="9780738442273" target="_blank">9780738442273</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Wiggins, Adam. "The Twelve-Factor App". Archived from the original on 13 June 2017. Retrieved 21 December 2017. <a href="https://web.archive.org/web/20170613060854/https://12factor.net/12factor.epub" target="_blank">https://web.archive.org/web/20170613060854/https://12factor.net/12factor.epub</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Horowitz, Ben (28 July 2016). "MRA, Part 5: Adapting the Twelve‑Factor App for Microservices". NGINX. Archived from the original on 22 December 2017. Retrieved 22 December 2017. <a href="https://www.nginx.com/blog/microservices-reference-architecture-nginx-twelve-factor-app/" target="_blank">https://www.nginx.com/blog/microservices-reference-architecture-nginx-twelve-factor-app/</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>"Beyond the Twelve-Factor App - Exploring the DNA of Highly Scalable, Resilient Cloud Applications". O'Reilly. Retrieved 22 December 2017. <a href="http://www.oreilly.com/webops-perf/free/beyond-the-twelve-factor-app.csp" target="_blank">http://www.oreilly.com/webops-perf/free/beyond-the-twelve-factor-app.csp</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> </ol>