···8899 public static string GenerateSnowflakeId(DateTime? createdAt = null)
1010 {
1111- if (createdAt?.Kind is not null and not DateTimeKind.Utc)
1111+ if (createdAt is { Kind: not DateTimeKind.Utc })
1212 createdAt = createdAt.Value.ToUniversalTime();
13131414 createdAt ??= DateTime.UtcNow;