I work in manufacturing, quite a bit of knowledge and experience regarding production processes, their history, means, etc. There are those with more in any given specific field, but from millwork to microcomputer design and metal foundries to metamaterials - I can hold down a conversation and wrap my head around engineering publications in each field.
I should remind everyone that most of today's devices operate upon principles which first appeared in theoretical papers in the 1940s or earlier. Imagine you have nearly blank checks for research and development, the best minds in the worlds lining up for a job, and authority to look over the shoulder of every university student looking to breakthrough to the next big thing.
We are not necessarily talking about making useful things, here - just achieving new feats for the sake of new feats (and patents…. But you don't patent it. You keep it secret as secret can be and patent it only when it appears other parts of the market could achieve it… China is doing absolutely nothing we have not already done). You can afford to poach some hot shot from a university, clone his whole lab, and hook him up with the most experienced machinists, chemists, etc.
Now, keep in mind - building an integrated circuit on par with today's microprocessors would be a tall order for such a team in the 60s, there's a lot of barriers we ran into along the way that required solving new chemistry and process control problems to realize production. However, that is also using mass manufacuring means suitable for producing tens of thousands of viable dies. If you only want 10 that work and can run a thousand cycles to get those ten that work - that's the cost of breakthrough programs.
Of course, software engineering is a whole art that has largely developed in the civilian world. You can't expect a team of such secretive people to have also built a comprehensive suite of software we would find intuitive - but in the world of advanced signal processing and the like, they could have made some badass things back in the day if they really wanted to.
Same with many metamaterials and other such things.
Do you think these people are so easy to contain using compartmentalization? They are going to bump elbows wherever they go.
Do you think the industrial complex behind the government is so easily suppressed by the words on a piece of paper?
There is an interesting game series: "BattleZone" which revolves around the space race being a rush between Russia and the U.S. to gather "biometal" from the Cythonian civilization's ruins. They were prevalent on Mars and their entire culture spilled over into the gods of the Greeks.
Then the second iteration gets into runaway black operations.
Something to think about. For every work of fiction, there is quite probably something real from which it drew considerable inspiration.