We need to talk about Feature Flags in Release Management
Tags: programming, featureflags, devops, beginners
Published: 2023-07-27 15:29:48

In the ever-evolving world of software development, there are tools and strategies that can drastically improve the process and outcomes of our work. One such technique, which many might not be familiar with, is release management. Specifically, we need to talk about the role of feature flags in release management.


## Understanding Release Management

Release management is the process of planning, scheduling, and controlling a software build through different stages and environments, including testing and deploying software releases. Think of it as the stage director in a theater production, ensuring each scene (or in our case, feature) runs smoothly and at the right time.

A prime example of the importance of release management is the infamous 1996 launch of the Ariane 5 Flight 501 by the European Space Agency. A minor software bug, overlooked in the release process, led to a loss of more than $370 million when the rocket self-destructed less than a minute after liftoff. Proper release management could have prevented this disaster.


## What are Feature Flags?

Imagine you're a magician, and you have the power to make certain parts of your act appear and disappear at will. That's what feature flags do in the world of software. They allow developers to enable or disable features in a software application without changing the code and redeploying the application. This technique is also known as feature toggling, feature switching, or feature flipping.


## The Intersection of Feature Flags and Release Management

Feature flags and release management intersect in a way that gives developers more control over their software's functionality at various stages of the release process. It's like having a 'rehearsal' and 'final performance' version of a play running simultaneously, with the director having the power to seamlessly swap scenes in and out.

For instance, a new feature in an application could be hidden behind a feature flag during the testing phase, allowing developers to thoroughly test it without impacting the end users. If an issue arises, the feature can be turned off immediately, preventing any negative user experiences.


## Why use Feature Flags in Release Management?

Feature flags provide numerous benefits in release management, from safe deployments to Experimentation and graceful degradation.

Safe deployments are like having a safety net. By deploying new features behind a feature flag, developers can gradually roll out the feature to a small set of users, reducing the risk of widespread issues. For example, Netflix is known for its use of feature flags to do 'canary releases', where new features are rolled out to a small audience before a full release.


## Hype or Value?

Feature flags aren't just a cool tool for developers, they are a game-changer for the entire software development process. This is essential to understand that Feature Flags help you ship and control your releases, but here’s how they are important to your daily workflow:

1. **Reduced Risk:** Feature flags reduce the risk of deploying new features. By hiding new features behind flags, we can test them thoroughly before making them available to all users.
2. **Faster Feedback:** By releasing features to a small subset of users, we can gather feedback and make improvements faster.
3. **Experimentation:** Feature flags enable A/B Testing, allowing us to test different versions of a feature to see which one performs better.
4. **Seamless Rollbacks:** If a feature isn't working as expected, feature flags allow for a quick rollback. This is much simpler and less risky than having to roll back an entire software release.What now?

In an era where customer expectations and competition are higher than ever, understanding and leveraging feature flags is no longer optional—it's essential. Imagine a situation where a major bug is discovered in a feature after it's been deployed. Without feature flags, the entire application might need to be taken down to fix the issue. But with feature flags, the faulty feature can be turned off while the rest of the application continues to serve the users uninterrupted.

The role of feature flags in release management is a topic that deserves more attention in the tech industry. As we have seen, they provide a powerful way to control feature releases, reduce risk, and ultimately deliver a better product to users.


## How to Implement Feature Flags

Implementing feature flags in your software can be achieved in several ways. You can:

1. **Build your own:** If you have the time and resources, you can code your own feature flags directly into your application. This gives you the most control, but it can be time-consuming and maintaining it is a huge commitment.
2. **Use a Library:** There are several libraries available that can help you implement feature flags, such as Togglz for Java or django-waffle for Python.
3. **Use a Feature Flag Management System:** For a more robust solution, you can use a feature flag management system like [Unleash](https://github.com/unleash), a free, open-source tool that gives you control over your feature flags without the heavy lifting.


## Start Now

### Start Unleash

With git and docker installed, it's easy to get started:

Run this script:

```
git clone git@github.com:Unleash/unleash.git
cd unleash
docker compose up -d
```

Then point your browser to `localhost:4242` and log in using:

username: `admin`
password: `unleash4all`

If you'd rather run the source code in this repo directly via Node.js, see the step-by-step instructions to get up and running in the contributing guide.


### Connect your SDK

Find your preferred SDK in our list of official SDKs and import it into your project. Follow the setup guides for your specific SDK.

For front-end SDKs, use:
URL: `http://localhost:4242/api/frontend/`
clientKey: `default:development.unleash-insecure-frontend-api-token`

For server-side SDKs, use:
Unleash API URL: `http://localhost:4242/api/`
API token: `default:development.unleash-insecure-api-token`

If you use a different setup, your configuration details will most likely also be different which you can find on the GitHub Repo.


## In Conclusion…

In an era where customer expectations and competition are higher than ever, understanding and leveraging feature flags is no longer optional—it's essential. Imagine a situation where a major bug is discovered in a feature after it's been deployed. Without feature flags, the entire application might need to be taken down to fix the issue. But with feature flags, the faulty feature can be turned off while the rest of the application continues to serve the users uninterrupted.

The role of feature flags in release management is a topic that deserves more attention in the tech industry. As we have seen, they provide a powerful way to control feature releases, reduce risk, and ultimately deliver a better product to users.