Feature flags with Azure App Configuration — quick notes
Feature flags (App Configuration) — quick notes
| Term | Definition |
|---|---|
| Feature flag | Variable with binary on/off state + associated code block |
| Feature manager (application-package concept) | App package managing flag lifecycle; distinct from the Azure portal Feature manager UI |
| Feature filter | Condition evaluated to determine flag state — for example, a time window or audience |
| Use case | Meaning |
|---|---|
| Code branch management | Dark deployment; avoid long-lived branches |
| Test in production | Internal users get real production experience |
| Flighting | Incremental percentage rollout |
| Instant kill switch | Disable with no rebuild/redeploy |
| Selective activation | Segment users |
| Portal creation choice | Purpose |
|---|---|
| Switch | Simple on/off control |
| Rollout | Progressive audience exposure |
| Experiment | Variants and controlled comparison |
Create path: App Configuration store > Operations > Feature manager > Create; then load and evaluate the flag through the platform's App Configuration provider and feature-management library.
Traps
- Refresh timing is provider- and configuration-dependent. The .NET provider's 30-second default is not a universal SLA.
- Plan retirement for temporary flags when they become obsolete; keep intentional long-lived flag paths tested and maintained.
Sources: https://learn.microsoft.com/en-us/credentials/certifications/resources/study-guides/az-400 · https://learn.microsoft.com/en-us/azure/azure-app-configuration/concept-feature-management · https://learn.microsoft.com/en-us/azure/azure-app-configuration/manage-feature-flags · https://learn.microsoft.com/en-us/azure/azure-app-configuration/howto-feature-filters · https://learn.microsoft.com/en-us/azure/azure-app-configuration/feature-management-dotnet-reference · https://learn.microsoft.com/en-us/azure/azure-app-configuration/reference-dotnet-provider · https://learn.microsoft.com/en-us/training/modules/implement-blue-green-deployment-feature-toggles/5-describe-feature-toggle-maintenance · https://learn.microsoft.com/en-us/devops/operate/progressive-experimentation-feature-flags