Is it possible to override a transitive dependency that a Tool will use? (at 'tool install' time or on the fly - I don't mind)
yes, you should be able to modify the classpath of the tool at execution time (except for named tools and the Clojure dependency itself - this is a known issue I'm currently working on)
Do you mean using -Scp ?
Ideally I could override a just a dep using this syntax clansi/clansi {:mvn/version "1.0.0"} and let tools.deps resolve the entire resulting tree as usual
you can do that via something like:
clj -Sdeps '{:aliases {:change {:override-deps {clansi/clansi {:mvn/version "1.0.0"}}}}}' -A:change -TwhateverThanks!
or if you're using a tools alias, -T:change:whatever