A **dev mask** refers to a mask used in the context of software development, typically as a debugging or diagnostic tool. These masks often allow developers to enable or disable certain features, log levels, or modes to facilitate testing and troubleshooting.

By applying a dev mask, developers can focus on specific parts of the code or behavior without interference from other components, thereby streamlining the debugging process. Dev masks can be implemented as configuration files, environment variables, or flags within the software.