Feature flag documentation for how to toggle features on/off for conducting trials

[MaxDiz]

Feature flags offer a convenient feature on/off toggle system. They enable teams to achieve continuous delivery by deploying features to production at smaller batches for controlled testing. We have (need to confirm) used them in the past for conducting randomized trials where one group of health workers may see a standard version of an app, and a second group of health workers would see a new feature, so that we could test the impact of that feature in a controlled way.

In order to make feature flags usable for the CHT community, we need to provide technical documentation and/or guidance on how to create, toggle and remove feature flags.

*May be worth investigating this open source tool for documentation that we can adapt (or perhaps as a product improvement in the future: https://github.com/Unleash/unleash)

cc: @isaacholeman

[SCdF]

We don't have any particular approach to this right now. It's challenging due to being offline first, and how our code is delivered to users.

In the past for some experiments we have segmented either with completely different installations, or by adding flags to their user document and having scriptable parts of the app (like the contact summary, or report filters) use that flag. However, this doesn't get you very far unfortunately.

[MaxDiz]

CHT forum post for reference on current capabilities/documentation: https://forum.communityhealthtoolkit.org/t/technical-docs-on-using-feature-flags/552/4

[MaxDiz]

transferring to new cht-docs repo

[michaelkohn]

https://docs.communityhealthtoolkit.org/apps/guides/updates/feature-flags/