I've seen companies use Headless Chrome and then WebAssembly to process files. You then lock down the Headless Chrome process. You're then "triple covered"; Web

I've seen companies use Headless Chrome and then WebAssembly to process files. You then lock down the Headless Chrome process. You're then "triple covered"; WebAssembly's limited context, JavaScript engine's limited context, and the Chrome process boundary itself. This is obviously "expensive" though. Doesn't scale very well.