I cannot disable App Transport Security (ATS) in Xcode 9.2. I have been (for years) disabling ATS when running builds against my local server environment like so:
Transp
On the navigator on the left-hand side of the screen in XCode, click your main project file, in which all the files and folders are stored. Click on the Info tab. Under "Custom iOS Target Properties", you used to see an option to change the App Transport Security Settings (ATS). It is not explicitly stated, but still available.
As you mouse over the options, you should see a +
in a small circle. Click on it. XCode will prompt you to create an "Application Category". IN that list that appears, scroll up and select "App Transport Security Settings".
Click on that option. Once that is created, it should prompt you to change the BOOL value (default should be "NO"). At the far right, you should see a set of up and down arrows. Click on this to change the BOOL to yes.