The most common and most likely answer to this crossword clue is the 9 letter word RETROFITS
I've seen this crossword clue in Financial Times
R
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Buddy explains!
The straight part
We know that "cutting-edge modifications" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cutting-edge modifications = retrofits.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RETROFITS mean?
RETROFITS noun- Something that has been retrofitted
- The act of retrofitting
- To add or substitute new parts or components to some device, structure etc., that were not previously available; to modernize
- To fix an older version (or older versions) as part of the same process of fixing the newest version; to backport