SQL vs NoSQL Databases: How to Choose
SQL vs NoSQL explained by data shape and access pattern, with concrete examples for relational, document, key-value, wide-column and graph databases.
Cloud & DevOps
What is Feature Flag?
Quick answer
A switch in software that turns a feature on or off for some or all users without deploying new code.
Feature Flag, explained
Feature flags, also called feature toggles, wrap new functionality in a condition that can be changed from a dashboard or configuration file. This separates deploying code from releasing a feature, so teams can ship unfinished work safely, turn features on for specific users, and switch off a problem feature instantly.
For example, a restaurant ordering platform might enable a new loyalty points screen only for staff and a few pilot restaurants, then roll it out more widely once feedback is positive. Feature flags also support A/B testing and canary releases. The main drawback is clutter: flags left in the code after a feature is fully launched add complexity and potential bugs, so teams should remove old flags on a regular schedule.
Related terms
A/B Testing
Comparing two versions of a web page, email, or feature with different groups of users to see which performs better.
CI/CDContinuous Integration and Continuous Delivery or Deployment: practices that automatically build, test, and release code changes.
Canary ReleaseA deployment approach that sends a new software version to a small share of users first, then expands it if no problems appear.
Guides that mention Feature Flag
How to Build a CI/CD Pipeline: Step-by-Step With Sample Config
A starter CI/CD pipeline with build, test and deploy stages, explained step by step, with sample GitHub Actions and GitLab CI configuration you can adapt.
What Is the Software Development Life Cycle (SDLC)? Phases Explained
The software development life cycle explained phase by phase, with the deliverables each stage produces and how modern agile and DevOps teams compress the cycle.