Looks like the issue is solved in the master branch of ionic-app-scripts.
You can clone the repo and build it yourself to apply the fix, until they publish a new release:
git clone https://github.com/driftyco/ionic-app-scripts
cd ionic-app-scripts
npm i
npm run build
Then copy all files/folders except node_modules and src to your project, under: node_modules/@ionic/app-scripts/.
Alternatively, you can download the package that I just compiled: https://dl.dropboxusercontent.com/u/35313543/ionic-app-scripts-0.0.27.tgz
I just applied this fix and it seems to be working good so far.
Update: I got rid of the Allocation failed - process out of memory error… but I’m still getting Maximum callstack exceeded
UPDATE #2: Nevermind, even using the master branch of ionic-app-scripts doesn’t fix this problem. But it doesn’t happen as often.