The Difference Between Continuous Delivery and Deployment

More than ever, modern development teams are seeing demands for speed and agility when developing software. Because so many facets of everyday life rely on software to run smoothly and numerous businesses need it to see ROI, developers are required to release quality software and updates rapidly.

One of the biggest challenges for developers is the pass-off between different siloes of the software development life cycle (code development, testing and QA, deployment, security, operations, and so on). Bottlenecks can become an issue if the handoff process between various stages isn’t streamlined.

To combat this issue, many software development teams turn to DevOps methodology for their processes. DevOps is a two-fold approach: training teams to communicate better, and improving processes through automation. Often, both pieces of this approach require updates to your tooling and company culture.

The CICD Pipeline, a DevOps Foundation

The best way to institute DevOps methodology within your organization is by building out a CICD pipeline. A CICD pipeline automates the various aspects of the software development process, especially the handoffs between different teams. 

The first half, “CI”, stands for Continuous Integration. CI focuses on the first part of software development. It includes managing a consistent source control version whenever developers commit new code snippets, automating tests to ensure that each new code snippet is well-written and error-free, and running build automation to turn the various code snippets into organized builds.

“CD”, on the other hand, can either stand for Continuous Delivery or Continuous Deployment. An organization will choose one of these two workflows to take place directly after Continuous Integration, depending on their business needs and level of DevOps proficiency.

What is the Difference Between Continuous Delivery and Continuous Deployment?

Continuous Delivery and Continuous Deployment are two different approaches to solve a similar pain point: automating the process of moving builds out of a code repository and into its next stage to prevent bottlenecks.

Continuous Delivery works to move the builds out of a central code repository and into a test environment. So, it generally requires two main components: an automation engine to move the build and automated testing to run on the builds once they reach the test environment. 

Continuous Deployment does all of this and then some - it goes a step further than Continuous Delivery by automating deployment into production after the builds have been tested in the test environment. 

Continuous Deployment is an evolved version of Continuous Delivery, removing the manual deployment to production. (This doesn’t mean that it’s better- every business has a unique structure and specific needs that could require either one or the other.) 

Prerequisites to Continuous Delivery and Continuous Deployment 

Batman and Robin. Sherlock and Watson. Lorelai and Rory. CI and CD. They’re all iconic duos who are nothing without each other. In order to have effective Continuous Delivery or Continuous Deployment, you need effective Continuous Integration.

Continuous Delivery or Continuous Deployment works best when Continuous Integration is in place to tee up the builds. Without CI, the code snippets might be disorganized from a lack of source code consistency, untested for initial bugs, and unconsolidated into builds. If that’s the case, then Continuous Delivery or Continuous Deployment would be pointless because it would just be passing scattered, poorly-tested code snippets downstream, leading to more work later! 

Advantages and Disadvantages of Continuous Delivery and Continuous Deployment

Continuous Delivery and Continuous Deployment both have advantages and disadvantages, so it’s important for every business to evaluate its unique situation before choosing which methodology to follow. We’ve compiled a helpful list to help you while considering your configurations.

Continuous Delivery Advantages

• Continuous Delivery provides a great launchpad for your organization’s CICD pipeline goals, regardless of the DevOps maturity level of your organization.

• It creates a smooth QA-Development integration and allows for easy wins, such as making iterative improvements to your automated testing cycles.

Continuous Delivery Disadvantages

• Continuous Delivery doesn’t cover the entire SDLC from end to end, meaning there will be decreased visibility and consistency once the builds leave the test environment.

• Requires a human being to facilitate the transfer between the test environment and production. If that human already has a lot on their plate, this could lead to bottlenecks.

Continuous Deployment Advantages

• Continuous Deployment speeds up the whole SDLC. For example, a feature can be passed downstream to production rapidly. Once the development team has written it, then it simply travels through the pipeline and straight into production.

• It creates better consistency and visibility because everything runs automatically, leading to better process documentation as automation engines run all aspects of each stage after the development team has written the initial code.

Continuous Deployment Disadvantages 

• Continuous Deployment relies on automated testing to catch errors. This means that if a business’s testing cycles aren’t mature enough, then errors could go into production undetected.

• It has a high initial cost, as it requires time from your personnel to gather together the correct documentation and establish the right processes.

• Continuous deployment can Include high maintenance costs, even after it’s been established. 

Is Continuous Delivery or Continuous Deployment Best for Your Development Team

With all of that said, you’re probably wondering which “CD” is best for your organization and business needs. Here are a few factors to keep in mind:

1. How mature are your testing processes?

If your testing cycles are mature and reliable, then you’re in a good place to consider Continuous Deployment. If not, you’re better off starting with Continuous Delivery.

2. Do you have thorough documentation for your SDLC?

If you don’t have straightforward documentation in place for your teams to use, then it’s better to start with Continuous Delivery. Continuous Delivery practices might even play a part in helping you move towards better documentation over time!

3. What does communication look like between teams?

How are your teams currently communicating? Are there still distinct siloes between the development, QA, and operations teams? If so, it might be a good idea to start with Continuous Delivery to begin facilitating better communication. 

4. How many stakeholders are required to approve handoffs?

If your business feels most comfortable with stakeholder checkpoints throughout the SDLC, then it’s probably best not to step into Continuous Deployment yet. But, if stakeholders are hoping to automate more and be confident in taking some of the approval processes off of their plates, then you might be in a good place for Continuous Deployment.

5. Is your organization ready for fast-paced cycles?

Are your team members able to respond to errors rapidly? Will you be able to deploy small changes to your softwares’ front-end users in a timely manner? If so, Continuous Deployment could be a good fit. But if these types of processes still need to be streamlined, it might be best to invest in Continuous Delivery instead.