Run only what changed

Use --affected to run a task only where your branch changed files, plus every task that depends on one of them.

vx run build --affected

On a branch, vx compares with the commit where it left your base branch (main). Add --dry to see what would run and why, without running it:

vx run build --affected --dry

would run:
  ▶  @demo/ui#build   cache miss — would exec   ea371b1a  ~9ms
                      affected: packages/ui/src/index.ts changed (an input)
  ▶  @demo/web#build  cache miss — would exec   3bc7cf82  ~5ms
                      affected: packages/ui/src/index.ts changed (an input), via @demo/ui#build

2 task(s) planned, 2 would run.
predicted: ~14ms wall · ~14ms total execution

---

To compare with another commit, name it:

vx run test --affected=origin/main
vx run test --affected=HEAD~1

On the base branch itself there is no default: run --all, and the cache runs only what changed, so CI on main needs only the current commit. On a branch, CI’s default one-commit checkout is enough: vx fetches the base commit and the history down to where the branch started, without file contents.

See --affected.