brew-cask: refusing to remove generic artifact outside {}: {

Error message

brew-cask: refusing to remove generic artifact outside {}: {}

What it means

On upgrade or uninstall, obsolete generic artifacts (recorded from a previous install but absent from the cask's current target list) are deleted. Before each removal mise re-verifies via path_starts_with_resolved_root that the recorded path still resolves inside the current Homebrew prefix; refusal protects against deleting files that now live outside the managed prefix.

Source

Thrown at src/system/packages/brew/cask.rs:2417

    };
    Ok(receipt
        .targets
        .into_iter()
        .filter(|record| receipt.generic.contains(&record.path))
        .collect())
}

fn remove_obsolete_generic_artifacts(
    previous_targets: &[CaskTargetRecord],
    current_targets: &[PathBuf],
) -> Result<()> {
    let prefix = prefix::prefix();
    for record in previous_targets {
        if current_targets.contains(&record.path) || !cask_target_record_matches(record)? {
            continue;
        }
        if !path_starts_with_resolved_root(&record.path, &prefix) {
            bail!(
                "brew-cask: refusing to remove generic artifact outside {}: {}",
                prefix.display(),
                record.path.display()
            );
        }
        if let Err(err) = remove_trusted_generic_target(&record.path) {
            warn!(
                "brew-cask: leaving obsolete generic artifact {} because its parent directories are mutable: {err:#}",
                record.path.display()
            );
        }
    }
    Ok(())
}

fn remove_trusted_generic_target(target: &Path) -> Result<()> {
    let expected_parent = resolved_parent(target)?;
    match remove_trusted_generic_target_from(target, &expected_parent) {

View on GitHub (pinned to 9dcfcaa0dc)

Solutions

Re-run the command with the same HOMEBREW_PREFIX that was active when the artifact was installed
If the prefix change is intentional, remove the obsolete artifact manually (path shown in the error) and clear the stale target record, then reinstall under the new prefix
Reinstall the cask under the current prefix so its records regenerate

Example fix

# before: prefix changed since install
HOMEBREW_PREFIX=/opt/homebrew mise uninstall foo  # refuses

# after: use the original prefix for the uninstall
HOMEBREW_PREFIX=/usr/local mise uninstall foo

Defensive patterns

Strategy: validation

Validate before calling

let prefix = homebrew_prefix();
for record in previous_targets {
    if !path_starts_with_resolved_root(&record.path, &prefix) {
        // prefix changed since install: migrate or clear the record before running the uninstall/upgrade
        eprintln!("stale target record outside prefix: {}", record.path.display());
    }
}

Prevention

Keep HOMEBREW_PREFIX stable, or reinstall casks immediately after changing it
Never hand-edit recorded target paths
Run uninstalls with the same prefix that was active at install time

When it happens

Trigger: HOMEBREW_PREFIX changed between the install that recorded the target and the current run; the prefix's symlink structure changed so the recorded path resolves differently; a hand-edited or corrupted target record.

Common situations: Switching prefixes (e.g. /usr/local to /opt/homebrew after an architecture migration) without reinstalling casks; moving a custom prefix; restoring a prefix from backup with different symlinks.

Related errors

AI-assisted analysis of jdx/mise@9dcfcaa0dc (2026-08-17). Data as JSON: /api/errors/9bdee3a0479362ef. Report an issue: GitHub.