How do the Borg adapt and assimilate?

Question

You see Borg drones or cubes being attacked and while some are being destroyed, they quickly adapt.

But HOW do they adapt mid-battle?

And how is technology described so they can assimilate it?

Every programmer knows that you can rarely just copy paste foreign code. The compiler will output error messages.

Research is not just brain power - which they have enough of due to the collective - it is also experiments and building things.

At least experiments need time.

Optimization is a field of its own in engineering aimed at making foreign technologies fit.

And they, too, need experimentation.

They might have time to assimilate, but they don't have time to adapt.

Is adaptation supposed to happen mid-battle?

When a ship is attacked or a drone?

Answer 1

Per the TNG movie ST: First Contact, we see the Borg use Nanoprobes to assimilate people. The series never dealt with the particulars, but the movie makes it clear they inject people with them, which makes them part of the collective shortly thereafter (it happens to several members of the crew in the movie).

Once a person has been assimilated, their knowledge is added to the collective. From The Best of Both Worlds Part II

RIKER: They couldn't have adapted that quickly.
PICARD [on viewscreen]: The knowledge and experience of the human Picard is part of us now. It has prepared us for all possible courses of action. Your resistance is hopeless, Number One.

They also have strength in numbers. We see in the same episode that they lose several drones before adapting. The dying drones transmitted data to the collective, allowing them to devise a defense. With thousands of drones, you can afford to brute force the problem by throwing drones at it until something works.

Answer 2

Nanotechnology & Knowledge from countless civilizations

Borg's nanotechnology is so advanced that it can modify warp drives to make them more powerful within few hours.

From Wikipedia:

Nanoprobes are microscopic machines that inhabit a Borg's body, bloodstream, and many cybernetic implants. The probes maintain the Borg cybernetic systems and repair damage to the organic parts of a Borg. They generate new technology inside a Borg when needed and protect them from many forms of disease. Borg nanoprobes, each about the size of a human red blood cell, travel through the victim's bloodstream and attach to individual cells. The nanoprobes rewrite the cellular DNA, altering the victim's biochemistry, and eventually form larger, more complicated structures and networks within the body, like electrical pathways, processing and data-storage nodes, and ultimately prosthetic devices that spring forth from the skin.

Also, it's a well known fact that Borg only assimilates sufficiently advanced civilization which makes sure that it gets new knowledge (like time travel).

We are the Borg. Lower your shields and surrender your ships. We will add your biological and technological distinctiveness to our own. Your culture will adapt to service us. Resistance is futile.

_{(Star Trek: First Contact)}

Combine these two and you've a formidable weapon.

P.S. Borg's adaption and assimilation capabilities get better over time. For example, Borg got nanoprobe technology after assimilating Species 139.

Answer 3

It would be cumbersome to be the Borg equivalent of a Swiss Army knife, with an attachment useful for any possible act of defense. Instead, it is more efficient to have the information for building any possible defense in short order. The Borg have assimilated the technology of many species, and have the knowledge ready to use. Clearly, their technology includes the means of replicating new items within seconds to minutes of needing them.

Answer 4

They are able to adapt during the battle because of the vast amount of technology they have amassed and the combined intellect of the hive mind.

Borg technology was a combination of technologies assimilated from other cultures and technology developed within the Collective in order to overcome obstacles to its goals. When confronted by a problem it could not solve with its existing resources and/or configuration, the entire Collective would work in concert to consider all possible solutions and implement the one determined to be the most efficient. By applying the unique skills of each drone to a task, the hive mind could engineer new technologies and solutions at a pace that would astound an individual. (https://memory-alpha.fandom.com/wiki/Borg)

If you have a great many options to work with, you will be more flexible than someone who has fewer weapons/tactics. Also, in the event that they do not already have what they need, all of them will combine their brainpower to come up with a solution. This also makes them more adaptable, because their problem-solving skills (when their intellect is combined) are second to none.