/// The persistence backend the service runs against.
///
/// The executable picks a driver at startup and hands it to ``Service``, which registers the
/// matching database as the default one. Repositories resolve that default and stay agnostic
/// of which backend is in use.
public enum Driver: Sendable {

    /// A MySQL/MariaDB server, reached with the given connection parameters.
    ///
    /// - Parameter configuration: the host, credentials, TLS posture, and pooling limits the
    ///   connection is opened with.
    case mysql(Configuration)

    /// An ephemeral, in-process SQLite database held entirely in memory.
    ///
    /// Nothing is written to disk, and all data is lost when the service stops — intended for
    /// local development and tests.
    case inMemory

}