Terms:

DevOps is a term that combines development (Dev) and operations (Ops), and refers to the culture, practices, and tools that aim to unify these two functions and deliver better software faster and more reliably. DevOps is not a specific role or technology, but rather a way of working that involves collaboration, automation, continuous delivery, and feedback across the entire application lifecycle.

DevOps emerged as a response to the challenges and inefficiencies of traditional software development and delivery methods, such as waterfall, which often resulted in siloed teams, long release cycles, poor quality, and high costs. DevOps seeks to overcome these issues by applying agile and lean principles to the entire software value stream, from ideation to operation.

Some of the benefits of DevOps include:

• Accelerating time to market: By automating and streamlining the processes of building, testing, deploying, and monitoring software, DevOps teams can deliver features and fixes to customers faster and more frequently.
• Adapting to the market and competition: By adopting a culture of experimentation and learning, DevOps teams can respond quickly to changing customer needs, feedback, and opportunities, and deliver value with minimal waste.
• Maintaining system stability and reliability: By implementing practices such as continuous integration, continuous testing, continuous delivery, infrastructure as code, and observability, DevOps teams can ensure that their software is always in a deployable state, meets quality standards, and performs well in production environments.
• Improving the mean time to recovery: By embracing a blameless culture of collaboration and communication, DevOps teams can identify and resolve issues faster and more effectively, minimizing the impact on customers and business outcomes.

DevOps influences the application lifecycle throughout its plan, develop, deliver, and operate phases. Each phase relies on the others, and the phases are not role-specific. In a true DevOps culture, each role is involved in each phase to some extent.

DevOps Phases:

• Plan: In the plan phase, DevOps teams ideate, define, and describe features and capabilities of the applications and systems they are building. They track progress at low and high levels of granularity—from single-product tasks to tasks that span portfolios of multiple products. Creating backlogs, tracking bugs, managing agile software development with Scrum or Kanban boards are some of the ways DevOps teams plan with agility and visibility.
• Develop: The develop phase includes all aspects of coding—writing, testing, reviewing, integrating code by team members—as well as building that code into artifacts that can be deployed into various environments. DevOps teams seek to innovate rapidly without sacrificing quality or productivity. To do that, they use productive tools such as code editors or IDEs (integrated development environments), automate mundane and manual steps such as compiling or packaging code using tools such as Maven or Gradle for Java or npm for JavaScript. They also iterate in small increments through automated testing using tools such as JUnit or Selenium for Java or Jest or Cypress for JavaScript. They also use continuous integration tools such as Jenkins or GitHub Actions to run tests and check code quality every time code is committed or merged into a shared repository.
• Deliver: Delivery is the process of deploying applications into production environments in a consistent and reliable way. The deliver phase also includes deploying and configuring the foundational infrastructure that makes up those environments. In the deliver phase, teams define a release management process with clear manual approval stages. They also set automated gates that move applications between stages until they’re made available to customers. Automating these processes makes them scalable, repeatable, controlled. DevOps teams use tools such as Ansible or Terraform for infrastructure as code (IaC), which allows them to provision and manage infrastructure using code rather than manual commands. They also use tools such as Docker or Kubernetes for containerization and orchestration which allows them to package applications with their dependencies into isolated units that can run on any platform. They also use tools such as Azure DevOps Services or AWS CodeDeploy for continuous delivery which allows them to deploy applications automatically to different environments based on predefined rules.
• Operate: Operate is the process of monitoring and maintaining applications in production environments. The operate phase also includes providing support for customers and users of the applications. In the operate phase, teams collect data on various aspects of application performance such as availability uptime response time error rate resource utilization customer satisfaction etc.

They also use tools such as Prometheus or Grafana for metrics collection, visualization, and alerting. They also use tools such as ELK Stack (Elasticsearch, Logstash, Kibana) or Splunk for log aggregation, analysis, and visualization. They also use tools such as Sentry or New Relic for error tracking and tracing. These tools help DevOps teams to gain insight into the health and performance of their applications, identify and troubleshoot issues, and optimize their resources and costs.

DevOps is not a one-size-fits-all approach, but rather a set of principles and practices that can be adapted to different contexts and goals. DevOps teams need to continuously learn, experiment, and improve their processes and tools to deliver value to their customers and stakeholders. DevOps is an ongoing journey that requires a mindset of collaboration, communication, feedback, and continuous improvement.