In a development environment, which type of file would you want to keep private to avoid security issues?

In a development environment, environment variable files are crucial for storing sensitive data such as API keys, database credentials, and configuration settings. The reason for keeping these files private is to prevent unauthorized access to sensitive information which, if exposed, could lead to severe security vulnerabilities. These files often contain information that should not be shared publicly, as they can allow unauthorized parties to gain access to critical systems and data.

YAML files, data templates, and custom scripts, while they may contain configuration details or workflows, generally do not hold sensitive information to the same extent as environment variable files. Thus, it's essential to safeguard environment variable files to maintain the integrity and security of the development environment and to protect sensitive information from potential breaches.