Suggest refactoring improvements for the following [language] code to enhance testability: [code snippet].
Identify opportunities to apply [architecture pattern] in the given [language] code: [code snippet].
Optimize the following [language] code for lower memory usage: [code snippet].
Refactor the given [language] code to improve its error handling and resilience: [code snippet].
Propose changes to the given [language] code to follow [SOLID or other design principles]: [code snippet].