Array ( [0] => {{short description|Set of software development practices}} [1] => {{pp-pc1}} [2] => [3] => '''DevOps''' is a methodology in the software development and IT industry. Used as a set of practices and tools, DevOps integrates and automates the work of [[software development]] (''Dev'') and [[IT operations]] (''Ops'') as a means for improving and shortening the [[systems development life cycle]].{{Cite web |last1=Courtemanche |first1=Meredith |last2=Mell |first2=Emily |last3=Gills |first3=Alexander S. |title=What Is DevOps? The Ultimate Guide |url=https://www.techtarget.com/searchitoperations/definition/DevOps |access-date=2023-01-22 |website=TechTarget |language=en}} DevOps is complementary to [[agile software development]]; several DevOps aspects came from the ''agile'' way of working. [4] => ==Definition== [5] => Other than it being a cross-functional combination (and a [[portmanteau]]) of the terms and concepts for "development" and "operations", academics and practitioners have not developed a universal definition for the term "DevOps".{{efn|Dyck et al. (2015) "To our knowledge, there is no uniform definition for the terms release engineering and DevOps. As a consequence, many people use their own definitions or rely on others, which results in confusion about those terms."{{Cite book |last1=Dyck |first1=Andrej |last2=Penners |first2=Ralf |last3=Lichter |first3=Horst |chapter=Towards Definitions for Release Engineering and DevOps |date=2015-05-19 |title=2015 IEEE/ACM 3rd International Workshop on Release Engineering |publisher=[[Institute of Electrical and Electronics Engineers|IEEE]] |page=3 |doi=10.1109/RELENG.2015.10 |isbn=978-1-4673-7070-7 |s2cid=4659735}}}}{{efn|Jabbari et al. (2016) "The research results of this study showed the need for a definition as individual studies do not consistently define DevOps."{{Cite journal |last1=Jabbari |first1=Ramtin |last2=bin Ali |first2=Nauman |last3=Petersen |first3=Kai |last4=Tanveer |first4=Binish |date=May 2016 |title=What is DevOps?: A Systematic Mapping Study on Definitions and Practices |journal=Proceedings of the 2016 Scientific Workshop |publisher=[[Association for Computing Machinery]]}}}}{{efn|Erich et al. (2017) "We noticed that there are various gaps in the study of DevOps: There is no consensus of what concepts DevOps covers, nor how DevOps is defined."{{Cite journal |last1=Erich |first1=F.M.A. |last2=Amrit |first2=C. |last3=Daneva |first3=M. |date=June 2017 |title=A Qualitative Study of DevOps Usage in Practice |journal=Journal of Software: Evolution and Process |volume=29 |issue=6 |pages=e1885 |doi=10.1002/smr.1885 |s2cid=35914007}}}}{{efn|Erich et al. (2017) "We discovered that there exists little agreement about the characteristics of DevOps in the academic literature."}} Most often, DevOps is characterized by key principles: shared ownership, workflow automation, and rapid feedback. [6] => From an academic perspective, [[Len Bass]], Ingo Weber, and Liming Zhu—three computer science researchers from the [[CSIRO]] and the [[Software Engineering Institute]]—suggested defining DevOps as "a set of practices intended to reduce the time between committing a change to a system and the change being placed into normal production, while ensuring high quality".{{Cite book |last1=Bass, Len |title=DevOps: A Software Architect's Perspective |last2=Weber, Ingo |last3=Zhu, Liming |year=2015 |publisher=Addison-Wesley |isbn=978-0134049847}} [7] => However, the term is used in multiple contexts. At its most successful, DevOps is a combination of specific practices, culture change, and tools.{{Cite journal |last1=Muñoz, Mirna |last2=Negrete Rodríguez, Mario |date=April 2021 |title=A guidance to implement or reinforce a DevOps approach in organizations: A case study}} [8] => [9] => ==History== [10] => Proposals to combine software development methodologies with deployment and operations concepts began to appear in the late 80s and early 90s.Chapman, M., Gatti, N: A model of a service life cycle, Proceedings of TINA '93, pp. I-205–I-215, Sep., 1993. [11] => [12] => Around 2007 and 2008, concerns were raised by those within the software development and IT communities that the separation between the two industries, where one wrote and created software entirely separate from those that deploy and support the software was creating a fatal level of dysfunction within the industry.{{Cite web |last=Atlassian |title=History of DevOps |url=https://www.atlassian.com/devops/what-is-devops/history-of-devops |access-date=2023-02-23 |website=Atlassian |language=en}} [13] => [14] => In 2009, the first conference named DevOps Days was held in [[Ghent]], [[Belgium]]. The conference was founded by Belgian consultant, project manager and agile practitioner Patrick Debois.{{Cite web |last=Mezak |first=Steve |date=25 January 2018 |title=The Origins of DevOps: What's in a Name? |url=https://devops.com/the-origins-of-devops-whats-in-a-name/ |access-date=6 May 2019 |publisher=devops.com}}{{Cite web |last=Debois |first=Patrick |date=9 October 2008 |title=Agile 2008 Toronto |url=http://www.jedi.be/blog/2008/10/09/agile-2008-toronto-agile-infrastructure-and-operations-presentation/ |access-date=12 March 2015 |publisher=Just Enough Documented Information}} The conference has now spread to other countries.{{Cite web |last=Debois |first=Patrick |title=DevOps Days |url=http://www.devopsdays.org/ |access-date=31 March 2011 |publisher=DevOps Days}} [15] => [16] => In 2012, a report called "State of DevOps" was first published by Alanna Brown at [[Puppet (software)|Puppet Labs]].{{Cite web |last1=Alana Brown |last2=Nicole Forsgren |last3=Jez Humble |last4=Nigel Kersten |last5=Gene Kim |date=2016 |title=2016 State of DevOps Report |url=https://dora.dev/research/2017-and-earlier/2016-state-of-devops-report.pdf |access-date=2024-04-24 |publisher=Puppet Labs, DORA (DevOps Research}}{{Cite web |title=Puppet - Alanna Brown |url=https://puppet.com/people/alanna-brown |access-date=2019-04-27 |publisher=Puppet Labs}} [17] => [18] => As of 2014, the annual State of DevOps report was published by [[Nicole Forsgren]], Gene Kim, Jez Humble and others. They stated that the adoption of DevOps was accelerating.{{Cite web |last1=Nicole Forsgren |last2=Gene Kim |last3=Nigel Kersten |last4=Jez Humble |date=2014 |title=2014 State of DevOps Report |url=https://dora.dev/research/2017-and-earlier/2014-state-of-devops-report.pdf |access-date=2024-04-24 |publisher=Puppet Labs, IT Revolution Press and ThoughtWorks}}{{Cite web |date=2015 |title=2015 State of DevOps Report |url=https://dora.dev/research/2017-and-earlier/2015-state-of-devops-report.pdf | access-date=2024-04-24 |publisher=Puppet Labs, Pwc, IT Revolution Press}} Also in 2014, Lisa Crispin and Janet Gregory wrote the book More Agile Testing, containing a chapter on testing and DevOps.{{Cite web |date=October 2014 |title=More Agile Testing |url=https://agiletester.ca/wp-content/uploads/sites/26/2014/09/TOC.pdf |access-date=2019-05-06}}{{Cite book |last1=Crispin |first1=Lisa |url=https://www.oreilly.com/library/view/more-agile-testing/9780133749571/ |title=More Agile Testing |last2=Gregory |first2=Janet |date=October 2014 |publisher=Addison-Wesley |isbn=9780133749571 |access-date=2019-05-06}} [19] => [20] => In 2016, the DORA metrics for throughput (deployment frequency, lead time for changes), and stability (mean time to recover, change failure rate) were published in the State of DevOps report. However, the research methodology and metrics were criticized by experts.{{Cite news |last=Turner |first=Graham |date=20 November 2023 |title=Report: Software Engineers Face Backlash for Reporting Wrongdoing |url=https://www.digit.fyi/report-software-engineers-facing-retaliation-for-reporting-wrongdoing/ |access-date=5 January 2024 |work=DIGIT |language=en}}{{Cite news |last=Saran |first=Cliff |title=Software engineers worry about speaking out - Computer Weekly |url=https://www.computerweekly.com/news/366560292/Software-engineers-worry-about-speaking-out |access-date=5 January 2024 |work=ComputerWeekly.com |language=en}}{{Cite news |title=75% of software engineers faced retaliation the last time they reported wrongdoing - ETHRWorldSEA |url=https://hrsea.economictimes.indiatimes.com/news/workplace/75-of-software-engineers-faced-retaliation-the-last-time-they-reported-wrongdoing/105335733 |work=ETHRWorld.com |language=en}}{{Cite web |last=Cummins |first=Holly |title=Holly Cummins on X |url=https://twitter.com/holly_cummins/status/1448357917384744964 |access-date=5 January 2024 |website=X.com}} In response to these criticisms, the 2023 State of DevOps report {{Cite web | last1=DeBellis | first1=Derek | title=2023 State of DevOps Report | url=https://cloud.google.com/devops/state-of-devops | access-date=2024-04-24 | last2=Lewis | first2=Amanda | last3=Villalba | first3=Daniella | last4=Farley | first4=Dave | publisher=Google Cloud DevOps Research and Assessment}} published changes that updated the stability metric "mean time to recover" to "failed deployment recovery time" acknowledging the confusion the former metric has caused.{{cite web |last1=DeBellis |first1=Derek |last2=Harvey |first2=Nathan |title=2023 State of DevOps Report: Culture is everything |url=https://cloud.google.com/blog/products/devops-sre/announcing-the-2023-state-of-devops-report |website=Google Cloud Blog |access-date=2024-04-24}} [21] => [22] => ==Relationship to other approaches== [23] => Many of the ideas fundamental to DevOps practices are inspired by, or mirror, other well known practices such as [[Lean manufacturing|Lean]] and [[W. Edwards Deming|Deming's]] [[PDCA|Plan-Do-Check-Act]] cycle, through to [[The Toyota Way]] and the [[Agile software development|Agile]] approach of breaking down components and batch sizes.{{Cite journal |last=Klein |first=Brandon Thorin |date=2021-05-01 |title=The DevOps: A Concise Understanding to the DevOps Philosophy and Science |url=https://www.osti.gov/biblio/1785164/ |language=English |doi=10.2172/1785164 |osti=1785164 |s2cid=236606284 |website=Osti.gov}} Contrary to the "top-down" prescriptive approach and rigid framework of [[ITIL]] in the 1990s, DevOps is "bottom-up" and flexible, having been created by software engineers for their own needs.{{Cite web |date=5 July 2020 |title=The History and Evolution of DevOps {{!}} Tom Geraghty |url=https://tomgeraghty.co.uk/index.php/the-history-and-evolution-of-devops/ |access-date=2020-11-29 |language=en-GB}} [24] => [25] => ===Agile=== [26] => {{Main|Agile software development}} [27] => The motivations for what has become modern DevOps and several standard DevOps practices such as automated build and test, [[continuous integration]], and [[continuous delivery]] originated in the Agile world, which dates (informally) to the 1990s, and formally to 2001. Agile development teams using methods such as [[extreme programming]] couldn't "satisfy the customer through early and continuous delivery of valuable software"{{Cite web |title=Principles behind the Agile Manifesto |url=https://agilemanifesto.org/principles.html |access-date=2020-12-06 |website=agilemanifesto.org}} unless they took responsibility for operations and infrastructure for their applications, automating much of that work. Because [[Scrum (software development)|Scrum]] emerged as the dominant Agile framework in the early 2000s and it omitted the engineering practices that were part of many Agile teams, the movement to automate operations and infrastructure functions splintered from Agile and expanded into what has become modern DevOps. Today, DevOps focuses on the deployment of developed software, whether it is developed using Agile oriented methodologies or other methodologies. [28] => [29] => ===ArchOps=== [30] => ArchOps presents an extension for DevOps practice, starting from [[software architecture]] artifacts, instead of source code, for operation deployment.{{Cite book |last1=Castellanos |first1=Camilo |title=Software Architecture |last2=Correal |first2=Dario |date=15 September 2018 |isbn=978-3-030-00760-7 |series=Lecture Notes in Computer Science |volume=11048 |pages=364–371 |chapter=Executing Architectural Models for Big Data Analytics |doi=10.1007/978-3-030-00761-4_24}} ArchOps states that architectural models are first-class entities in software development, deployment, and operations. [31] => [32] => === Continuous Integration and Delivery (CI/CD) === [33] => {{Main|CI/CD}} [34] => Automation is a core principle for achieving DevOps success and CI/CD is a critical component.{{Cite book |last1=Humble |first1=Jez |title=Continuous Delivery: reliable software releases through build, test, and deployment automation |last2=Farley |first2=David |date=2011 |publisher=Pearson Education Inc. |isbn=978-0-321-60191-9}} Plus, improved collaboration and communication between and within teams helps achieve faster [[time to market]], with reduced risks.{{Cite journal |last=Chen |first=Lianping |year=2015 |title=Continuous Delivery: Huge Benefits, but Challenges Too |journal=IEEE Software |volume=32 |issue=2 |pages=50–54 |doi=10.1109/MS.2015.27 |s2cid=1241241}} [35] => [36] => === Mobile DevOps === [37] => {{Main|Mobile DevOps}} [38] => [39] => Mobile DevOps is a set of practices that applies the principles of DevOps specifically to the development of mobile applications. Traditional DevOps focuses on streamlining the [[software development process]] in general, but [[Mobile app development|mobile development]] has its own unique challenges that require a tailored approach.{{Cite book |last1=Tak |first1=Rohin |title=Mobile DevOps: Deliver continuous integration and deployment within your mobile applications |last2=Modi |first2=Jhalak |date=2018 |publisher=Packt Publishing |isbn=9781788296243 |pages=12–18}} Mobile DevOps is not simply as a branch of DevOps specific to mobile app development, instead an extension and reinterpretation of the DevOps philosophy due to very specific requirements of the mobile world. [40] => [41] => ===Site-reliability engineering=== [42] => {{Main|Site reliability engineering}} [43] => In 2003, [[Google]] developed [[site reliability engineering]] (SRE), an approach for releasing new features continuously into large-scale high-availability systems while maintaining high-quality end-user experience.{{Cite book |last1=Beyer |first1=Betsy |title=Site Reliability Engineering |last2=Jones |first2=Chris |last3=Petoff |first3=Jennifer |last4=Murphy |first4=Niall Richard |date=April 2016 |publisher=O'Reilly Media |isbn=978-1-4919-2909-4}} While SRE predates the development of DevOps, they are generally viewed as being related to each other. [44] => [45] => ===Toyota production system, lean thinking, kaizen=== [46] => {{main|Toyota Production System}} [47] => Toyota production system, also known under the acronym TPS, was the inspiration for [[lean thinking]] with its focus on [[continuous improvement process|continuous improvement]], [[kaizen]], flow and small batches. The [[Andon (manufacturing)|andon cord principle]] to create fast feedback, swarm and solve problems stems from TPS.[https://opensource.com/article/18/11/analyzing-devops Analyzing the DNA of DevOps], Brent Aaron Reed, Willy Schaub, 2018-11-14.{{Cite book |last1=Gene Kim |title=The DevOps Handbook: How to Create World-Class Agility, Reliability, and Security in Technology Organizations |last2=Patrick Debois |last3=John Willis |last4=Jezz Humble |date=2016}} [48] => [49] => ===DevSecOps, shifting security left=== [50] => DevSecOps is an augmentation of DevOps to allow for security practices to be integrated into the DevOps approach. Contrary to a traditional centralized security team model, each delivery team is empowered to factor in the correct security controls into their software delivery. Security practices and testing are performed earlier in the development lifecycle, hence the term "[[Shift-left testing|shift left]]". Security is tested in three main areas: static, software composition, and dynamic. [51] => [52] => Checking software statically via [[static application security testing]] (SAST) is [[white-box testing]] with special focus on security. Depending on the programming language, different tools are needed to do such static code analysis. The software composition is analyzed, especially libraries, and the version of each component is checked against vulnerability lists published by [[Computer emergency response team|CERT]] and other expert groups. When giving software to clients, library licenses and their match to the license of the software distributed are in focus, especially [[copyleft]] licenses. [53] => [54] => In dynamic testing, also called [[black-box testing]], software is tested without knowing its inner functions. In DevSecOps this practice may be referred to as [[dynamic application security testing]] (DAST) or penetration testing. The goal is early detection of defects including [[cross-site scripting]] and [[SQL injection]] vulnerabilities. Threat types are published by the [[OWASP|open web application security project]], e.g. its TOP10,{{Cite web |title=OWASP TOP10 |url=https://owasp.org/Top10/ |url-status=live |archive-url=https://web.archive.org/web/20230608171837/https://owasp.org/Top10/ |archive-date=June 8, 2023 |access-date=June 8, 2023}} and by other bodies. [55] => [56] => DevSecOps has also been described as a cultural shift involving a holistic approach to producing secure software by integrating security education, security by design, and security automation.{{Cite book |last=Wilson |first=Glenn |title='DevSecOps: A leader's guide to producing secure software with compromising flow, feedback and continuous improvement' |date=December 2020 |publisher=Rethink Press |isbn=978-1781335024}} [57] => [58] => ==Cultural change== [59] => DevOps initiatives can create cultural changes in companies{{Cite report |title=Emerging Technology Analysis: DevOps a Culture Shift, Not a Technology |publisher=Gartner}} by transforming the way [[Information technology operations|operations]], [[Software developer|developers]], and [[Software testing|testers]] collaborate during the development and delivery processes.{{Cite web |last=Loukides |first=Mike |date=7 June 2012 |title=What is DevOps? |url=http://radar.oreilly.com/2012/06/what-is-devops.html |publisher=[[O'Reilly Media]]}} Getting these groups to work cohesively is a critical challenge in enterprise DevOps adoption.{{Cite web |title=Gartner IT Glossary {{ndash}} devops |url=http://www.gartner.com/it-glossary/devops/ |access-date=30 October 2015 |website=Gartner}}{{Cite book |last1=Jones |first1=Stephen |url=https://ueaeprints.uea.ac.uk/id/eprint/59131/4/Accepted_manuscript.pdf |title=Proceedings of the 2nd International Workshop on Quality-Aware DevOps - QUDOS 2016 |last2=Noppen |first2=Joost |last3=Lettice |first3=Fiona |date=21 July 2016 |isbn=9781450344111 |pages=7–11 |doi=10.1145/2945408.2945410 |s2cid=515140}} DevOps is as much about culture as it is about the toolchain.{{Cite web |last=Mandi Walls |date=25 September 2015 |title=Building a DevOps culture |url=https://www.oreilly.com/ideas/building-a-devops-culture |publisher=O'Reilly}} [60] => [61] => ===Microservices=== [62] => Although in principle it is possible to practice DevOps with any architectural style, the [[microservices]] architectural style is becoming the standard for building continuously deployed systems. Small size service allows the architecture of an individual service to emerge through continuous refactoring.{{Cite conference |last1=Chen |first1=Lianping |last2=Ali Babar |first2=Muhammad |date=2014 |title=2014 IEEE/IFIP Conference on Software Architecture |publisher=IEEE |pages=195–204 |doi=10.1109/WICSA.2014.45 |isbn=978-1-4799-3412-6 |chapter=Towards an Evidence-Based Understanding of Emergence of Architecture through Continuous Refactoring in Agile Software Development |book-title=The 11th Working IEEE/IFIP Conference on Software Architecture(WICSA 2014)}} [63] => [64] => ===DevOps automation=== [65] => It also supports consistency, reliability, and efficiency within the organization, and is usually enabled by a shared code repository or version control. As DevOps researcher Ravi Teja Yarlagadda hypothesizes, "Through DevOps, there is an assumption that all functions can be carried out, controlled, and managed in a central place using a simple code."{{Cite SSRN |title=DevOps and Its Practices |last=Teja Yarlagadda |first=Ravi |date=9 March 2021 |ssrn=3798877}} [66] => [67] => ==== Automation with version control ==== [68] => Many organizations use [[version control]] to power DevOps automation technologies like [[virtual machines]], containerization (or [[OS-level virtualization]]), and [[CI/CD]]. The paper "DevOps: development of a toolchain in the banking domain" notes that with teams of developers working on the same project, "All developers need to make changes to the same codebase and sometimes edit even the same files. For efficient working, there has to be a system that helps engineers avoid conflicts and retain the codebase history,"{{Cite thesis |last=Morisio |first=Maurizio |title=DevOps: development of a toolchain in the banking domain |date=16 April 2021 |access-date=16 August 2021 |degree=laurea |url=https://webthesis.biblio.polito.it/18120/ |journal=Politecnico di Torino}} with the [[Git]] version control system and the [[GitHub]] platform referenced as examples. [69] => [70] => ==GitOps== [71] => GitOps evolved from DevOps. The specific state of deployment configuration is [[version-control]]led. Because the most popular [[version-control]] is [[Git]], GitOps' approach has been named after [[Git]]. Changes to configuration can be managed using [[code review]] practices, and can be rolled back using version-controlling. Essentially, all of the changes to a code are tracked, bookmarked, and making any updates to the history can be made easier. As explained by [[Red Hat]], ''"visibility to change means the ability to trace and reproduce issues quickly, improving overall security."''{{Cite web |title=What is GitOps? |url=https://www.redhat.com/en/topics/devops/what-is-gitops |access-date=2023-03-30 |website=www.redhat.com |language=en}} [72] => [73] => ==See also== [74] => * [[DataOps]] [75] => * [[DevOps toolchain]] [76] => * [[Twelve-factor app]] [77] => * [[Infrastructure as code]] [78] => * [[Lean software development]] [79] => * [[Value stream]] [80] => [81] => ==Notes== [82] => [83] => {{notelist}} [84] => [85] => ==References== [86] => [87] => {{reflist|1=30em}} [88] => [89] => ==Further reading== [90] => [91] => * {{Cite book |last1=Davis |first1=Jennifer |title=Effective DevOps : building a culture of collaboration, affinity, and tooling at scale |last2=Daniels |first2=Ryn |date=2016-05-30 |publisher=O'Reilly |isbn=9781491926437 |location=Sebastopol, CA |oclc=951434424}} [92] => [93] => * {{Cite book |last1=Kim |first1=Gene |title=The DevOps handbook : how to create world-class agility, reliability, and security in technology organizations |last2=Debois |first2=Patrick |last3=Willis |first3=John |last4=Humble |first4=Jez |last5=Allspaw |first5=John |date=2015-10-07 |isbn=9781942788003 |edition=First |location=Portland, OR |oclc=907166314}} [94] => [95] => * {{Cite book |last1=Forsgren |first1=Nicole |title=Accelerate: The Science of Lean Software and DevOps: Building and Scaling High Performing Technology Organizations |last2=Humble |first2=Jez |last3=Kim |first3=Gene |date=27 March 2018 |publisher=IT Revolution Press |isbn=9781942788331 |edition=First}} [96] => [97] => {{Software engineering|state=expanded}} [98] => {{Authority control}} [99] => [100] => {{DEFAULTSORT:Devops}} [101] => [[Category:Agile software development]] [102] => [[Category:Software development process]] [103] => [[Category:Information technology management]] [104] => [[Category:Software development]] [] => )
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DevOps

DevOps is a set of principles, practices, and tools that aim to improve collaboration and communication between software development teams (Dev) and IT operations (Ops). It focuses on breaking down silos, automating processes, and streamlining workflows to deliver software more efficiently and reliably.

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It focuses on breaking down silos, automating processes, and streamlining workflows to deliver software more efficiently and reliably. The term "DevOps" was coined in 2008 and has gained widespread adoption in the software industry since then. DevOps encompasses various practices such as continuous integration, continuous delivery, and infrastructure as code. These practices promote faster development cycles, shorter time to market, and increased stability and quality of software releases. DevOps encourages a cultural shift where development and operations teams work together closely throughout the software development lifecycle. Collaboration is key, as it helps align business objectives, enhance software delivery speed, and improve customer satisfaction. DevOps also emphasizes the importance of automation to eliminate manual and repetitive tasks, reduce errors, and improve efficiency. The adoption of DevOps has numerous benefits for organizations. It enables faster feedback loops, allowing teams to detect and address issues earlier in the development process. It also facilitates faster deployments and rollbacks, reducing the impact of failures. Moreover, DevOps promotes a continuous learning and improvement mindset, leading to a more agile and resilient software delivery process. The Wikipedia page on DevOps provides a comprehensive overview of the topic, including its history, key principles, practices, and associated tools. It also explores the challenges and benefits of adopting DevOps and highlights notable case studies and success stories. Additionally, the page covers related topics such as DevSecOps (integrating security into DevOps), Site Reliability Engineering (SRE), and DevOps in specific industries like cloud computing and mobile app development.

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