Prompt

Please implement a feature flag system for my application with the following specifications:

### Current Deployment
- **Description**: {describe deployment process}

### Use Cases
- **Planned Feature Flag Uses**: {list specific use cases for feature flags, e.g., A/B testing, gradual feature rollouts, etc.}

### Technology Stack
- **Current Stack**: {list current technologies being used, e.g., React, Node.js, etc.}

### Design Requirements
1. **Flag Storage and Management**: Outline how feature flags will be stored (e.g., database, config files) and managed (e.g., admin UI).
2. **Client-Side Implementation**: Describe how flags will be accessed and utilized in the client application.
3. **Server-Side Implementation**: Explain how the server will handle flag evaluations and serve the appropriate features.
4. **Flag Evaluation Logic**: Define the logic for determining which features are enabled based on the flags.
5. **Gradual Rollout Strategies**: Provide strategies for gradually rolling out features to a subset of users (e.g., percentage-based rollout).
6. **Cleanup Procedures**: Describe how to safely remove or disable feature flags after they are no longer needed.

### Success Criteria
- The feature flag system should allow for easy enabling/disabling of features without redeploying the application.
- It should support at least two use cases (e.g., A/B testing and gradual rollout).
- The implementation should handle edge cases, such as flags being misconfigured or unavailable.

### Edge Cases
- Describe how the system will behave if a feature flag is missing or if there are conflicts between flags.
- Provide fallback mechanisms in case of errors during flag evaluation.