In developing software, we often work in different environments, which helps us separate out data and allows for testing away from live data used by customers. Separating environments also allows us to test more freely and do controlled releases of new features where some users can test out the feature, find any bugs, and give feedback before they are fully released. Environments are a combination of the data they have access to and the code being run. The flow is normally that code is added into dev when approved, passed onto staging for testing and into production when fully ready for customer use.
Let's take a look at the three main environments that developers use in the release of software:
This is the first in the pipeline of environments, and where most developers spend most of their time. It should use mock or seeded data that allows for experimentation when building. This allows people to make changes without worrying about affecting real data.This means code in this environment is more likely to be unstable and could still have issues.
This environment should closely match to the real-life data used in production. This allows for user acceptance testing (UAT) and quality assurance testing as well (QA). This environment is key to releasing quality software. By having an area to test that uses close to real data but is still isolated from the actual business data allows for the freedom and accuracy of testing that is important for releasing apps to real users.
This is the real deal, where actual user data is stored and where actions have business consequences. This should be the most stable of environments, where only fully tested features should make it in this far, having gone through PR reviews and testing by QA and Users in staging to be confirmed working.
Whilst some early-stage startups and companies yet to release might not maintain such a strict separation, almost all developers use at least a development and a production environment. Let's look into some of the reasons why below.
Despite PR reviews, pair programming, and unit testing, mistakes happen and errors arise in the development of software, by separating these environments we can move as many of these mistakes to testing data that has no impact on business. Extra testing steps mean we can feel more confident in deploying software that is robust and ready for the end-user to use.
By offering a staging environment to business or selected users with near-real data, software can be well optimised for real use cases and incorporate better feedback before general release. By getting user acceptance testing (UAT), changes can easily be made before having to reach the production environment, but users can test data in structures they recognise without as much instability as in dev. This results in an improved final product and a better user experience when it is released.
By being able to not only test in a development environment, but also in a staging environment, you can test on more accurate data sizes for your main application. That query that ran fine on a small sample of data might not work on a production-size dataset. By adding a staging environment in between, you can identify any problems before they are released, eliminating downtime caused by errors.
Staging environments create a great place for security testing to take place. If these test where run in a production environment they could expose real data or cause a disruption to services. Staging allows security assessments without real-world risks.
Separating development, staging, and production environments is a foundational software engineering practice that dramatically improves quality, reliability, and safety. By creating a controlled progression from idea to live feature, teams reduce risk and improve user satisfaction. Whether you're a small startup or a large enterprise, this structure enables smoother releases and long-term scalability.
