Keeping SDKs up to date

dv install records what you asked for, not only what it installed. That is what dv update works from.

dv install 10.0         # tracks "the newest 10.0"
dv install lts          # tracks "the newest LTS", across majors
dv install 10.0.402     # an exact version: a pin, never moved
cd ~/code/app && dv install   # tracks this repository's global.json

Months later:

$ dv update
  10.0  10.0.402 → 10.0.405
  lts   10.0.402 → 10.0.405
  /Users/you/code/app/global.json
        9.0.310  up to date
installed 10.0.405
removed 10.0.402 — superseded, and nothing else needs it; `dv install <version>` gets one back

What is tracked

Source	From	Moves on update
explicit	dv install 10.0, lts, 10.0.4xx, …	yes, within what it names
explicit, pinned	dv install 10.0.402	never
global-json	dv install with no version, in a repository	as that file’s rollForward allows
default	dv default 8.0	yes, within what it names
runtime	dv runtime install aspnetcore@8.0	yes, within what it names

A global.json requirement is re-read on every update: edit the pin and the next update follows it; delete the file and dv stops tracking it, and says so.

dv list --format json shows everything tracked. The state lives in tracked.json in dv’s home — plain JSON you can read.

What is removed

An update removes only what it supersedes: the SDK a requirement resolved to before the update, once the update has moved that requirement to a newer one — and only if nothing else still resolves to it. Another requirement, the default, and the current directory’s global.json all keep an SDK.

So 10.0 moving from 10.0.402 to 10.0.405 removes 10.0.402, while an exact pin, or an SDK some other line still uses, stays.

An SDK no requirement tracks is never removed. The report lists it, with the commands to track or remove it:

not tracked, left alone: 8.0.426 — `dv install <version>` tracks one,
`dv uninstall <version>` removes it

Nothing is removed silently: every removal is named, with how to get it back. A removed SDK’s archive stays in the download cache, so reinstalling it is instant until you run dv cache prune.

dv update --dry-run     # what would change, changing nothing
dv update --no-prune    # install updates, remove nothing

What dv cannot see

dv knows only the global.json files it was told about. If a repository you never ran dv install in pins exactly the SDK one of your tracked lines moves away from — 10.0.402 while 10.0 moves to 10.0.405 — that SDK is removed unless you run the update from inside the repository. Run dv install once in each repository you want kept, or check dv update --dry-run first.

Uninstalling

dv uninstall 10.0 removes the SDK and stops tracking 10.0 and any exact pin on that version. If another requirement still accepts it — lts, say — dv tells you the next update would install it again.