Software Development Insights | Daffodil Software

All About Feature Flags: Key Benefits, Use Cases, & Top Tools

Written by Neha Dhiman | Dec 20, 2024 6:30:00 AM

In 2023, Netflix rolled out its new ‘Profiles’ feature where users could add up to 5 other users to the same subscription. This feature, considering its large-scale impact, was not rolled out for all users at once. Instead, they leveraged “Feature Flags”, or “Feature Toggles” to release the feature to a small subset of its users, that too in a phased manner. This gave Netflix the freedom to optimize user experience based on real-user feedback and the flexibility to switch off the toggle in case something didn’t go right. 

While there are many other instances of how organizations are leveraging feature flags, it’s important to have a clear picture of what Feature Flags really are. Which is exactly what we’ll be discussing in the blog today.

Explore the widespread benefits of Feature Flags, future trends around the same, and how they are the key to risk-free releases and innovation.


What are Feature Flags?


There’s constant pressure on software development teams to release new features while ensuring both quality and security. Releasing features to all users at once can be a double-edged sword. While it may seem convenient, even a small bug in production can lead to a fallout when things go live. This is where Feature Flags come into play.

Feature Flags have become a game-changer for organizations to deploy changes with confidence. Feature Flags, Feature Toggles, or Flippers are a software development technique. These allow developers to switch features on or off, i.e. enable or disable functionalities at the runtime without deploying any new code. These offer the utmost flexibility and visibility to release features, test in production, and roll back if something does not function properly. The aim is to minimize the risk and maximize agility. 

In other words, Feature Flags offer an alternate route for developers to test features. By decoupling deployment from release, teams can work on complex systems without the risk of hampering the entire code, keeping the features disabled/hidden until they are confident enough to push them to everyone.


How are Feature Flags Different From Traditional Boolean Flags?


Boolean Flag or Truth Flag is a variable that can only be of 2 states - either true or false. They are used to turn an object's function or behavior on or off.

In the past, developers used Boolean Flags which had a toggle feature however, it lacked advanced functionalities. This is where Feature Flags upped the game for product managers and QA teams. With these advanced toggle flags, they could perform additional actions, run experiments, validate releases, and do much more without writing any additional code.


Understanding Trunk-Based Development (TBD) and The Role of Feature Flags


Trunk-Based Development (TBD) is a modern software development approach. It emphasizes working on a “trunk” i.e. a single, shared branch of code. This approach helps to minimize the complexity of managing multiple code branches and allows for faster feature rollouts. In TBD, feature flags minimize the risk of breaking the code. These decouple code deployment from feature release and help developers in rolling features in a controlled manner.

This is particularly beneficial for UI/UX design, as it enables designers and developers to collaborate closely and make changes to user interface elements without affecting the code.


Benefits of Feature Flags & How They Enable Risk-Free Releases



1. Progressive Rollouts

A key advantage of utilizing Feature Flags is that they allow the developers to push things to live gradually. This ability helps them to make features live for a smaller set of users instead of all at once. Once the performance is monitored and no bug is found, it can be released to everyone using the software application. Software development companies usually take advantage of this gradual roll-out function to test the market and expand their release. 

Let’s say you’re a part of a of an e-commerce company and you’re about to roll out a new payment gateway integration. With a Feature Flag, you can release the feature to just 10% of the users, gather feedback, and monitor for any bugs. This phased approach is known as “canary release” and helps to reduce risk when introducing new changes.

2. A/B Testing and Experimentation

A/B testing allows businesses to make data-driven decisions. Feature Flags enable the toggle with which you can switch features on and off for a particular audience segment. This way you can test the functionality with different user sets and see how they interact with it. In the end, what you’ll have is a refined product that appeals to your users. 

For instance, a social media platform can test its designs by segmenting the audience based on their demographics or behaviors. Once the feedback pours in, product teams can assess what works and what doesn’t in terms of user engagement. As one segment responds, the toggle switch can be used for another segment, giving you a complete review of your designs.

This ensures the feedback is real-time and based on real-users’ experience with your design and not just assumptions.

3. Seamless Hotfixes & Rollbacks

There’s always a chance for software deployments to fall out of place. This is where the flexibility of Feature Flags ensures that your users are unaffected. The capability to roll back features when things don’t align with your goals makes Feature Toggles a go-to option for organizations. Instead of rolling back entire deployments, you simply have to toggle the flag and the feature will be removed from your application.

This step will minimize the dissatisfaction levels of customers, prevent any downtime, and buy time for your team to fix the issue, if any.


4. Facilitating DevOps and Continuous Integration/Continuous Deployment (CI/CD)

In modern DevOps and CI/CD workflows, Feature Flags have become an indispensable tool to deploy changes at any time. Teams can push features in phases without waiting for a 100% development of a bigger change. This helps to test the feature in parts and simultaneously work on enhancements. This not only reduces the time between development and production but also helps to avoid conflicts or downtime. In short, faster releases and less risk. 


5. Better Collaboration Across Teams

Feature toggles help to enhance collaboration between operations, development, and testing teams. With the freedom to work independently, Developers can keep adding features, software testing can take place simultaneously, and real-time feedback can also be gathered. Customers can also enjoy the upgraded features and teams can continue working on expanding them enabling an agile approach to development. 

ALSO READ: Why Every Application Needs a Regular UX Audit

 

Real-Life Use Cases of Feature Flags


1. Spotify: A/B Testing for Personalization

When it comes to A/B testing, leading music streaming platform Spotify, relies heavily on Feature Flags. With millions of users on the platform, it’s important for Spotify to perform experience testing before it impacts users in any way. Right from the user interface to personalized recommendations - the platform ensures that each feature is thoroughly tested in a phased manner before full-scale deployments. 

Spotify segments users into controlled, experiment groups and monitors how users are responding to a change, i.e. if they are abandoning the application from where the feature was launched, or are exploring the same, if the feature working well or is there a performance dip? This way the brand can keep improving its user experience and ensure minimal risk.


2. Canva: Scaling to 50 million uploads 

In 2022, Canva shared a blog that highlighted how the company scaled its media service infrastructure. While there were many technical challenges, Feature Flags became a crucial tool that enabled them to test their migration from MySQL to DynamoDB media service. Feature toggles helped them to isolate changes and roll back when required. This gave them the space to experiment, deploy incrementally, and avoid downtime. The results were astonishing. Canva’s media service stored over 25 billion user-uploaded media and the platform enabled 50 million uploads daily.


3. Meta: Phased Feature Rollout

Meta leverages toggling and partial roll-outs when launching any new feature. It first releases it to a small group and then expands to other users to detect any unforeseen issues.

In 2015, when Meta rolled out its live-streaming feature, it did so in a phased manner. At first, a small set of users from selected regions could use the feature, later when the feature was refined and optimized, it was made available for its entire user base.

In 2018, Meta reported that it utilizes over 10,000 active feature flags across its various products.


4. Netflix: Continuous Experimentation 

Netflix keeps employing Feature Flags to enable continuous experimentation and A/B testing, The giant regularly uses A/B tests in order to determine which thumbnails, recommendations, or content would result in the best user engagement.
In 2023, Netflix began its beta testing of video game streaming service to test and track logs, bugs, crashes, and other deployment roadblocks.


5. Specsavers

Specsavers utilizes feature flagging in their in-house application offering sight and hearing services. The application witnesses over 80% of appointment bookings and with every new feature roll-out, Specsavers performs experimentation until the desired changes are met.

 

The Rise of Feature Flags: Industry Insights and Statistics


Feature Flags have gained much traction in recent times with the rise of DevOps. As CI/CD practices leap, so do newer ways to execute faster releases. 


  • In Atlassian’s Rising the Flag report, 87% of respondents agree that having a killswitch or a toggle feature reduces the chances of downtime for customers. 

  • According to 2023 Feature Management Impact Report by Split, 92% of respondents agree that software feature management is important for digital platform development.

  • As per a survey by LaunchDarkly, organizations without feature flags struggle with long and complex rollbacks. Whereas, 100% of IT and software professionals that implement feature flags have seen improvements since the time their company adopted the methodology.


Top Feature Flag Tools Sorted By Offerings

 


1. For Full-Scale Enterprise & Automated Deployments

  • LaunchDarkly offers advanced targeting, user segmentation, and experimentation. It also offers canary and blue/green deployments, making it an excellent choice for large-scale complex roll-outs and roll-backs.

  • Harness integrates deployment automation and feature flagging in one platform. Its all-in-one deployment pipeline reduces manual processes and risks during feature rollouts.

2. For Experimentation & A/B Testing

  • Split.io offers deep A/B testing capabilities. They offer options like attribute-based user segmentation, feature variation, and detailed insights into feature performance. This makes them perfect for data-driven organizations.

  • Optimizely offers feature toggles with advanced optimization tools for personalization, user segmentation, and multi-platform testing. Best-suited for experiment-driven product development companies.

3. For Lightweight & Open-Source Solutions

  • FeatureFlagCo is an open-source solution offering basic-level feature flag management options. If you’re a smaller team looking for easy-to-work-on platforms, FeatureFlagCo is your go-to option.

  • Unlike FeatureFlagCo, Unleash is highly scalable and customizable. It helps teams with the ability to manage flags across environments. Great for teams that want to self-host their feature flags, especially in cloud-native environments.


4. For Java-Centric Teams

  • Togglz is a Java-based library that supports multiple backends (such as in-memory, Redis, database). While it lacks advanced features, it’s still a good option for teams who need simple flagging in Java applications.

 

Why Feature Flags Are Essential for Agile Teams


As more and more organizations are adopting agile methodologies, Feature Flags have become even more essential than ever. Teams can freely test, release, and manage features fast giving their organizations the agility to beat the competition.

Microsoft’s Azure DevOps team utilizes toggles across their cloud offerings. For a brand as huge as them, they cannot afford to have their services down for a long period. With Feature Flags, they could roll back the changes, resume the services, and fix the issue while users continue to use other services.

 

Getting Closer to The Future with Feature Flags


Feature Flags are becoming a central part of product strategy. Today, feature toggles are used in UI/UX design, pricing models, service offerings, and a lot more. One such field where Feature Flags are witnessing a rapid expansion is artificial intelligence (AI) and machine learning (ML). These models suggest content to users and have become a game changer for the streaming giant. This surely hints at more collaboration between these two in the future.

Leverage our AI/ML development services to harness the full potential of feature toggles in your AI-driven applications.

When it comes to software development, Feature Flags will continue to expand its reach alongside advancements in edge computing, cloud computing, and microservices architecture.

Serverless platforms such as AWS Lambda and many Google Cloud Functions help businesses to deploy code in isolation - which means Feature Flags will be a huge part of the space.

With Feature Flags becoming a crucial part of the software development lifecycle, it could surely be a stepping stone in the future of autonomous feature delivery.

ALSO READ: 17 Latest UI/UX Trends That Are Shaping Modern Digital Experiences

 

Overcoming Key Challenges with Feature Toggles


A few challenges that are looming around the implementation of Feature Flags:

  • Complexity in Managing Flags at Scale: With organizations expanding at pace, managing a large number of feature flags can be daunting. It can lead to ‘flag sprawl’ or accumulation of flags over time making it hard to manage or track the same. A way to control the same is by utilizing platforms that offer a centralized dashboard to manage the entire slack. You can try Unleash or LaunchDarkly which offer effective Feature Flag management.

  • Technical Debt: If not handled correctly, Feature Flags can add technical debt to the codebase. Hence it is necessary to keep a check on the same and perform regular audits to clean up flags whenever required. A Flag expiration date can also be set so they don’t accumulate on the code unnecessarily.

  • User Experience Concerns: Ensure users are not subjected to too many changes at once. One needs to monitor the behavior of the toggle and disable the ones that are not adding any value to the user experience.

 

ALSO READ: What is Technical Debt & How It Affects Your Business

 

Conclusion: Why Your Software Development Needs Feature Flags


Experimentation and innovation are key to driving software development success, and Feature Flags offers exactly that and more. It enables change - both at speed and effectively - minus the risk of failed releases. These help businesses stay agile and customer-focused at all times.

Whether you’re a growing startup or a global enterprise platform, implementing Feature Flags into your workflow will help you build with confidence, iterate at pace, and deliver exceptional software at scale.

Want to learn more about how Feature Flags can elevate your release strategy? Connect with our experts in a no-obligation consultation session and start your journey toward risk-free releases and continuous innovation.