jdx/mise · error

brew-cask:{}: only font-only casks without lifecycle hooks a

Error message

brew-cask:{}: only font-only casks without lifecycle hooks are supported on linux

What it means

On Linux, mise's brew-cask support only handles casks that install fonts and nothing else — no apps, binaries, pkgs, installers, generic artifacts, completions, or preflight/postflight lifecycle hooks. validate_platform_support checks exactly that shape under cfg(target_os = "linux") and bails with the cask token otherwise, because macOS GUI install machinery (.app bundles, pkgs, launchservices) cannot be reproduced on Linux.

Source

Thrown at src/system/packages/brew/cask.rs:5047

fn validate_platform_support(cask: &Cask, artifacts: &CaskArtifacts) -> Result<()> {
    #[cfg(target_os = "linux")]
    {
        let font_only = !artifacts.fonts.is_empty()
            && artifacts.apps.is_empty()
            && artifacts.binaries.is_empty()
            && artifacts.command_wrappers.is_empty()
            && artifacts.pkgs.is_empty()
            && artifacts.installers.is_empty()
            && artifacts.generic.is_empty()
            && artifacts.completions.is_empty()
            && artifacts.generated_completions.is_empty()
            && artifacts.preflight_steps.is_empty()
            && artifacts.postflight_steps.is_empty()
            && !has_lifecycle_hook(cask, "preflight")
            && !has_lifecycle_hook(cask, "postflight");
        if !font_only {
            bail!(
                "brew-cask:{}: only font-only casks without lifecycle hooks are supported on linux",
                cask.token
            );
        }
    }
    #[cfg(not(target_os = "linux"))]
    let _ = (cask, artifacts);
    Ok(())
}

fn platform_unavailable_state(cask: &Cask, artifacts: &CaskArtifacts) -> Option<PackageState> {
    validate_platform_support(cask, artifacts)
        .err()
        .map(|err| PackageState::unavailable(err.to_string()))
}

fn artifact_target(value: &Value, values: &[Value]) -> Option<String> {
    values

View on GitHub (pinned to 6f52dcdf99)

Solutions

1. On Linux, remove or gate the brew-cask entry (e.g. move it into a macOS-specific config such as a `[tools]` section scoped by platform, or use mise's per-OS config files).
2. Install the tool through a native channel on Linux: a brew formula if the CLI exists as one, an aqua/github backend, or the system package manager.
3. Confirm the cask really is non-font (brew info --cask): if it is fonts-only without hooks it should pass — a failure then worth reporting as a bug.

Example fix

# before — shared mise.toml breaks Linux
[tools]
"brew-cask:visual-studio-code" = "latest"

# after — scope cask to macOS via per-platform config (mise.macos.toml or darwin guard)
# mise.linux.toml keeps native tools only

# keep macOS-only casks out of Linux configs
if [ "$(uname -s)" != "Darwin" ]; then
  grep -q 'brew-cask:' mise.toml && echo 'move brew-cask entries to a macOS-specific config (e.g. mise.macos.toml)'
fi

When it happens

Trigger: Running `mise use brew-cask:<token>` / `mise install` for a standard macOS app cask on a Linux machine: the artifact inventory contains apps/binaries/pkgs or the cask declares preflight/postflight hooks, failing the font_only conjunction at src/system/packages/brew/cask.rs:5047.

Common situations: Shared mise.toml between a Mac and a Linux box pinning a brew-cask; CI on Linux inheriting a teammate's cask entries; font casks that also ship a helper binary (disqualified by the non-empty binaries list).

Related errors

• brew-cask: completion executable '{}' is ambiguous: {}
• brew-cask: failed to generate {} completions from {}: {}
• brew-cask: completion target '{}' must not contain '..'
• brew-cask: invalid completion target '{target_name}'
• brew-cask: invalid completion target '{}'

AI-assisted analysis of jdx/mise@6f52dcdf99 (2026-08-22). Data as JSON: /api/errors/1ba94172c5b7c77e. Report an issue: GitHub.