What are CI and CD

With Continuous Integration (CI) and Continuous Delivery (CD) the goal is to quickly deliver code changes or update software in an agile and automated way. Here we explain more about what they are and how the two systems work together

As we described in another article, both CI and CD are part of the DevOps methodology. They enable collaboration and the automation of workflows. Just as industry automates production to save time and money, you want to be able to automate web development. Repetitive processes can be made more efficient when automated and human errors minimized. But to kick off automated workflows you need skilled web developers with access to the right tools. Methods are also needed to enable wider collaboration

A development team often consists of several people with different roles and working methods. To make collaboration easier you need ways to communicate and coordinate work. Developing code often requires various platforms and tools. That calls for a way to integrate and validate code across those platforms. You simply need to make it easier to make code changes. This is where Continuous Integration (CI), or continuous integration, and Continuous Delivery (CD), or continuous delivery, come into the picture

Continuous Integration (CI) – automates build and testing

Traditionally, developers often work on multiple branches, where different projects or parts of a project have their own branch. Eventually several branches are merged into a product or service. In Continuous Integration (CI), or continuous integration, the development team uses version control and integrates their work frequently into the same place, a master branch. By splitting the code into multiple branches, or parts, you can carry out faster release cycles.

Each code change is then built and verified using automated tests to detect errors as early as possible. This way you can quickly and early get a signal if something in the code is wrong or needs to be redone. Errors or bugs are also often more manageable the earlier they are discovered and fixed. The testing phase thus functions as quality assurance of the final product.

Because continuous integration is about the actual building and testing that happens before delivery, it is also a prerequisite for continuous delivery. Where continuous integration ends, continuous delivery picks up. Both play an important role in moving forward in the development and delivery process.

Continuous Delivery (CD) – methods that automate the entire path to production

Continuous Delivery (CD), or continuous delivery, ensures that there is an automated way to transfer and deliver code changes between different platforms and tools. As we mentioned earlier, different platforms and tools are often required to develop code. Because of this, there is also a need for a way to merge the code from the different programs into a kind of code package. CD therefore means that you automate the release process. The automation itself consists of functions that deploy code to production. This can, for example, be a person, a business rule or a test that determines when this happens. To minimize the impact of potential errors, you can limit the delivery to a subset. Users then get access to a few new features and more are released over time.

Once a release has been deployed, the configuration phase begins. Here you specify your runtime environment using a manifest, which describes how a server should be set up and what should be installed on it. In this way you can automate continuous distribution, that is, ensure the server has the same setup for subsequent releases. At the same time it is important to continuously monitor the process – also from a user perspective. You may need to ask questions such as; Is everything working as it should? What do performance and resource usage look like? Do we need more or less computing power – do we need to scale up or down?

How the process works

When you want stable applications that can be updated quickly and without disruptions, it's important to establish a consistent and automated way to build, package and test. That is also why continuous integration and continuous delivery play an important role in the development process.

The process often begins with defining how to handle configuration and version control. This way you gain better oversight of which features and which code are ready for testing and production. Testing, in turn, often takes place at the end of each sprint. The key here is automated tests where, with the help of status codes, you become aware of any issues or verify that you did the right thing. Finally, continuous delivery takes over and is the automation that gets applications out to deployment environments.

6 advantages for you as a customer:

• With automation we can minimize the number of errors that can occur. Not least because with CI and CD you work in iterative loops. For you as a customer this means a cost-effective way of working that saves both time and money
• A technical advantage is that CI and CD can release small code packages at the same time. Small code packages are easier to manage than large ones, especially if errors are discovered. This too can save the project both time and money
• With fast release cycles, errors can be detected at an early stage and therefore fixed more quickly. This leads to us being able to maintain a higher work pace and experiencing fewer major operational disruptions. For you, this means your customers are less affected, and thus your whole business
• Both maintenance and updates are an important part of creating successful products. With CI and CD everything becomes simpler because there is a clear work process and many automated workflows. The gain is that your product/service becomes more competitive
• Since a large part consists of tests, CI and CD are an excellent way to get continuous feedback. Not only from the client but also from the internal team. With feedback you have the opportunity to improve and develop your tools, methods and processes. As a customer, this ultimately leads to better products
• When different systems in a process can be adapted, integrated and exchange information, it becomes possible to tailor and automate the flow. This can make your product/service unique and provide significant competitive advantages

What is the difference between an agile way of working, CI/CD and DevOps

By now you have hopefully gotten a better grasp of what continuous delivery and integration mean. If you've also read the article about DevOps and heard about agile ways of working, you might start wondering what the actual difference is. Don't they resemble each other quite a bit? Yes, to some extent. Although an agile way of working, CI/CD and DevOps are different, some things do resemble one another. Broadly speaking, it's about improving and developing smart work processes to create better products and services.

So how do they actually differ? With an agile way of working the focus is on the development process itself. With DevOps the focus is on culture and collaboration, while CI/CD is more about methods and tools. All three support each other in the development and delivery process and contain useful components that digital projects can benefit from. At Limetta we have experience both using and introducing methods, tools and processes to increase the quality of our clients' digital products and services.

Summary

• CI/CD is a method for delivering code to development environments faster by automating many of the different steps in the development process. Continuous Integration can be seen as the initial step where the code is created and tested as early as possible to determine whether the code is good enough or not. Continuous Delivery, on the other hand, is about the actual delivery of the code package. The shared goal is to automate as much as possible.
• When working in shorter cycles, where you test and release a smaller amount of code, it becomes easier to identify potential problems. It also prevents multiple people from working on the same code that then has to be merged.
• To be able to quickly deliver stable products and services at a high pace, both fast and flexible methods are required. By integrating different systems it is possible to automate processes, analyze, and make smarter decisions. CI and CD give us the methods and tools to achieve that.
• A CI/CD process can look slightly different depending on which tools are used. Regardless of how it looks, you will save both time and money if you adopt more automated workflows.

If you want to know more about CI, CD and how they relate to the DevOps methodology you can read our article on that topic. If you wish to increase the pace of change and raise the quality of your digital product/service - don’t hesitate to contact us! We help you based on your unique needs and circumstances.

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