If you work in DevOps, you may have heard, or be familiar with, continuous integration and continuous deployment. Often, people use these terms interchangeably, but this is incorrect. 

Consider that you wish to implement a change to your web application – for simple changes, these are often made directly. But when you’re considering improving your development workflow, you’ll want to be able to stage these changes, test them in a separate environment, and deploy them – all without causing your site to be temporarily inaccessible to end-users.

In essence, continuous integration and continuous deployment are two related, but separate processes for automated deployment to make changes to code. They are ways to change code in order to keep things smooth, with less need for manual testing and changing. While they do relate to each other, each is a distinct concept that needs to be understood. 

In this guide, we’ll break down what these terms mean, how they’re different, the benefits of taking advantage of them in your workflow, and how to implement them properly in WordPress – so, let’s dive right in.

What Are Continuous Integration And Continuous Deployment?

As we mentioned previously, they are both methods to deploy changes to code. If you need to make some changes to the code of a site, you will need to understand both continuous integration and deployment to do so. 

However, to make matters potentially a bit confusing, they can work together, with each aspect, integration, and deployment representing different factors. You have to use continuous integration as part of continuous deployment, but you may opt out of continuous deployment, however.  So, they are not the same, and they need to be understood independently. Let’s dive into looking at exactly what each of these terms mean.

What Is Continuous Integration?

Continuous integration is the first element of a good CI/CD setup in your development workflow, and it is the automated method of combining code versions and validating results. This is particularly useful the more frequently you make changes, as you can create a CI pipeline that automatically builds and tests changes before you merge them. 

This is especially true if you’ve developed automated tests. The benefit of CI is that developers can focus on development while the key tests run in the background to catch any changes that conflict with any other existing code. This can be in the form of deploying to a staging environment or simply running automated tests in the background. 

What Is Continuous Deployment?

Continuous deployment (CD), on the other hand, is the last element of a CI/CD workflow. Once the modifications have been integrated and tested via your CI pipeline, the next step is to deploy your new release. Many developers still do this manually, which is a huge waste of time. Fortunately, if you use a service like RunCloud to manage your server infrastructure, you can easily automate your deployments making it possible to seamlessly release your code as frequently as you’d like. 

► No more sleepless nights thinking of launch days and pushing individual features. 

► Deploy with no downtime for your users and easily roll back changes if you spot anything that’s acting up in production that wasn’t caught during your testing. 

Note: There is another term that is sometimes used: continuous delivery. This is very similar to continuous deployment in that it forms an important part of the development approach involved with ensuring that changes can be pushed at any time. This means that building, testing, and releasing software can take place more efficiently. 

What Is The Difference Between Continuous Integration And Continuous Deployment?

Effectively, continuous integration is how to make the code updates work for the developers, assisting them in the implementation of code changes into the main branch. Continuous deployment is about getting the code to the end-user in a way that doesn’t interfere with the branch, and testing to make sure that changes are automatically implemented without issue. They both relate to each other, in that continuous integration plays a role in continuous deployment, but deployment is the step to get the results to the end-user. 

How Can Continuous Integration And Continuous Deployment Work Together?

You need continuous integration if you want to do continuous deployment. In that, if a commit is being deployed regularly to production, it needs to be working, and you need to be sure of that. Continuous integration allows you to ensure that it works. So, if you want to do continuous deployment of regular commits, you need to do continuous integration. 

However, if you do not have regular changes, you may not need to do continuous deployment; rather, you may choose to opt for continuous delivery and integration. The integration ensures all code changes work, and delivery requires manual approval of the implementation of the changes. Deployment becomes more useful when you are comfortable with the testing process, and you have more regular changes to implement. 

Why Use Continuous Integration?

Continuous integration is useful for you and your team to ensure that code changes work. There are several reasons you should use this approach, which we outline now:

Advantages Of Continuous Integration

  • Fewer Bugs — Because of the automated tests, bugs get caught early on, and there is less chance of breaking. 
  • Easy Building Of Release — As you are ensuring that integration matters are taken care of early, the release can be built much easier. 
  • Less Context Switching — Developers immediately know when something breaks, allowing them to fix it prior to changing tasks. 
  • Less Testing Costs — Continuous integration servers can handle hundreds of tests per second. This reduces your costs considerably. 
  • Less Documentation — If you just use continuous integration without continuous deployment, you will have less need to document each and every automatic deployment. 
  • Less Need For Top Level Testing — Similarly, if you forgo continuous deployment, you don’t need as much top-level testing to ensure that your automatic deployment works. In fact, you have more manual control over the process.

Why Use Continuous Deployment?

With continuous deployment, you make your life considerably easier in the long run. It allows for efficient deployments, and given that you trust your testing, it means that you can spend more time developing instead of worrying whether your changes will work outside of production. 

Here are the reasons to consider using continuous deployment:

Advantages Of Continuous Deployment 

  • Fast Development — There is no need to pause development for each and every release. Rather, the pipelines get automatically triggered to make changes. 
  • Less time-consuming tasks — Continuous deployment automates a range of tasks, saving a lot of time. 
  • No Daily Merging Of Changes — If you just use continuous integration, you have to take care of merges every day, but continuous deployment does this for you.
  • No tests for each feature — Just using continuous integration requires tests for each new feature. Continuous deployment takes care of that for you. 
  • Less Risky Releases — With continuous deployment, you can release small batches of code, which are easier to fix. 
  • Daily Improvements — The end users get to experience constant improvement on a daily basis. 

How To Adopt Continuous Deployment?

If you want the benefits of continuous deployment, but so far are only using continuous integration and delivery, how easy it would be to adopt continuous deployment will vary depending on where you are with your project status. 

When starting a project, you can implement continuous deployment as soon as possible. You can automate deployments before having end-users, to ensure all things are running smoothly, and generally check that everything is working fine. You can increase the testing and when eventually you are content with the deployment process, you can then launch with a whole continuous deployment process in place. 

If your project is already running, and end-users are already present, there are some things to consider changing:

  1. Start with continuous integration and delivery, in order to have more control and checks over the process. 
  2. Then create basic tests for automatic execution, to avoid making things too difficult. 
  3. Then you can start automating deployments so that eventually all deployments are done automatically. 
  4. When you are ready for full continuous deployment you need to ensure that everyone is ready and aware of the nature of any changes to the code, as this can affect customers. Constant planning is also required as are top-level testing capabilities. 

The Best CI/CD Tools We Recommend 

There are multiple tools out there to do the heavy lifting with both continuous integration and continuous deployment. Generally, they help facilitate the integration and automated deployment of code. 

If you already use RunCloud to manage cloud infrastructure, we offer built-in Atomic Deployment, so you don’t have to worry about setting up, configuring, and paying for yet another service to handle your continuous integration and deployment needs. 

That being said, other big names that provide services for continuous integration and deployment are Jenkins, CircleCI, and GitLab, among many others. 

Jenkins is an open-source automation server, with building and integration processes, and it supports hundreds of plugins to help with integration as well as deployment.

With CircleCI, you are able to have an automated pipeline, from building to deployment, and it is compatible with many other programs, including Jenkins, GitLab, and others. It also hosts continuous integration on the cloud or behind a firewall on your own server.

GitLab is a Git repository manager and lets you trigger builds, run tests, or deploy code at each push or commit. 

Find what tools you require to help with your continuous integration and deployment needs. 

How Does Continuous Integration Or Continuous Deployment Work With WordPress?

Generally, WordPress projects are a bit different, due to the lack of suites for built-in units and integration tests. However, these processes can still apply to WordPress. The main concern for developers when it comes to WordPress is ensuring everything works without affecting the speed of pages. Continuous integration and continuous deployment can take care of this. 

Do bear in mind the nature of the structure will be affected if the project has a standalone theme or plugin, or WordPress’s feature themes. 

Generally, you would first need to build your dependencies. 

Second, you test your code. If you use continuous integration and continuous deployment, you can test within your site. Different developers use different approaches, but it is something that can be done with WordPress. 

Finally, you can deploy. When you deploy in WordPress, it is most likely you are deploying a plugin, theme, or full site. 

RunCloud’s Atomic Deployment feature is platform-independent, which means it works with WordPress, but it also works with other platforms, such as Laravel. PHP management tools are essential for WordPress. 

After Action Report – Implement CI/CD In Your Development Workflow Today

Continuous integration and continuous deployment are two terms that are used interchangeably, in part because they are often linked together. However, we explained the different natures of each of these things. Whether you wish to use continuous deployment is up to you, but it is a good way to save a lot of time and effort, once set up. 

It is generally better if you can trust your testing capabilities or are in the early stages of project development. Consider learning more about how RunCloud’s Atomic Deployment can help with your site. Here are some sources you can find out more about Atomic Deployment:

Do you have any specific questions about continuous integration and continuous deployment? Or think we’ve missed something worth including in this post? Join the conversation by leaving a comment below. 💬