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Mendix-Agil-Feature-Flags

Introduction

In the realm of low-code development with Mendix, delivering robust applications and incorporating large user stories efficiently remains paramount. While Mendix streamlines many aspects of development, the challenge of integrating large features persists. But could there be a more agile way?

The Traditional Approach in Mendix

Even within Mendix's streamlined environment, when significant user stories span across releases, developers often resort to working in isolation. The intention is to merge modules or branches once the entire feature is refined. This approach, however familiar, brings with it the risk of code misses due to delayed merges or potential delays in subsequent releases if a feature requires extended QA.

A New Approach with Feature Flags

This is where the feature flag strategy shines. Instead of holding back modules or branches until they're perfect, integrate parts of your major feature in consecutive releases. How? Conceal the new functionality behind a feature flag. By doing this, you ensure that end users can only access the feature when you're ready to showcase it. At the same time, this allows QA testers in Mendix to toggle the feature on for incremental testing, maximizing efficiency.

Design Considerations in Mendix

When implementing this in Mendix, you will combine the functionality of enumerations, constants and nanoflows (or microflows).

  • The enumeration will define a list of flagged features.
  • The constant will contain a list of enabled features (e.g. comma or semicolon separated) for the current environment.
  • The nanoflows (or microflows) will take a single parameter of enumeration value – the feature in question – and will evaluate whether the constant includes the value in the enabled features list. This flow will return a boolean result representing whether the feature is activated.

You will then be able to use the activated boolean to control the logic in the parent flow to enable or disable functionality in the current environment. This setup can be easily queried and integrated throughout your Mendix app, providing a cohesive system to manage feature availability.

Benefits

Adopting the feature flag strategy in Mendix offers:

  • Risk Reduction: Lessen the potential for code misses from prolonged merges.
  • Flexibility: Incrementally introduce parts of a feature without disrupting the user experience.
  • Efficient QA: Empower testers to validate features progressively, ensuring meticulous testing.

Conclusion

Mendix revolutionizes low-code development, and with the integration of practices like feature flags, developers can further enhance agility and efficiency. If you're a Mendix enthusiast, how have you navigated the challenges of large feature integration?