As for the caliber of engineer required, considering this isn't "write an OS" but rather "remove or disable a 10 counter" it's likely that the work could be done by a junior - or someone out of the country for that matter. It's not the highest of high end jobs."
From the order:
(1) it will bypass or disable the auto-erase function whether or not it has been enabled; (2) it will enable the FBI to submit passcodes to the SUBJECT DEVICE for testing electronically via the physical device port, Bluetooth, Wi-Fi, or other protocol available on the SUBJECT DEVICE and (3) it will ensure that when the FBI submits passcodes to the SUBJECT DEVICE, software running on the device will not purposefully introduce any additional delay between passcode attempts beyond what is incurred by Apple hardware.
Arguably, (1) and (3) might be fairly simple, although given that I haven't seen the IOS source code, I can't say for certain.
(2) on the other hand, seems fairly unlikely to be currently implemented - although it may be implemented in debug code that can be turned enabled elsewhere in the code.
All of the above - regardless of how the requirements are implemented - would need to be validated and survive regression testing and quality control before the code could be loaded onto the phone.
"Essentially, if Apple's employees refuse to do the work, Apple would likely have to fire them with cause. End of benefits, end of vested shares, end of it all. It's unlikely that any engineers would take that risk (unless they got very, very bad legal advice)."
Software engineers capable of doing this type of coding at Apple's scale are in high demand. In all likelihood, no engineer who quit Apple over this would be unemployed for longer than they chose to be.
Similarly: Because of the caliber of software engineer required, it would quite likely be difficult to replace them on short notice.
You're watching 3 (at minimum) distinct - but related - fights, and really, it's more akin to a chess match:
Court of public opinion - seems like apple may be winning here
Court of Law - Apple seems to have solid arguments, but the law is fungible. It'll be years before we know the outcome
Political fight on Capital Hill - the jury is still out on this. The public won't get a real sense of where this _really_ lies before November, at the earliest.
Each of these will turn, at least in part, on the others. For example, if the FBI wins the political fight and gets the legislation they want, the court battle will likely be moot. Whether or not they get that legislation is at least partially dependent on the results of the elections, etc.
We've just seen the finish of the opening, and now we're seeing the beginning of the middle game.
That's it. This is a textual representation of a 2048 bit RSA key. generate a CSR and a public key, and you can plug it into any Apache web server. Or use it to sign email. Or sign applications. And those signatures will be valid on any system with the public key installed as a certificate authority.
If you were to see Apple's private key exported like this one is, it would look very similar, although (hopefully) 4096 bits instead of 2048 (twice as long). And it might be DSA, instead of RSA. I'm certain it's stored in a _very_ tightly controlled environment.
This key fits trivially into a paste buffer. So would Apple's. You could print it and type it in by hand if you were so inclined. Or take a picture and OCR it. And if that happens - just once - it potentially puts the security of every Apple device on the planet at risk.
Now, this is a simplistic example. I'm sure Apple's implementation utilizes a hierarchy of similar keys, with limited uses, etc, all signed by a single, master key which is stored in tamper-proof hardware, requires multiple people to get to it, etc. But that master key only has to get exported once to the wrong individual to compromise the entire system.
If passed, it would be exceedingly easy to intercept, record, and subsequently expose their never-ending corruption.
Actually, if you start from the premise that it's already exceedingly easy for TLA's to intercept, record, and subsequently expose the never-ending corruption of our elected political heroes, it explains a great many things.