Andon: Problem Visualization

Andon (行灯) means “lantern” - a signal board that makes quality problems immediately visible to the entire team.

Core Principle

Problems must be visible the moment they occur. Hidden failures compound into catastrophes.

In Batuta, Andon manifests as the diagnostics engine that provides colored, at-a-glance status for every stack component and pipeline phase.

Andon in Batuta

Stack Health Dashboard

# Real-time health across all components
batuta stack status

# Component      | Signal | Detail
# ---------------|--------|----------------------------
# trueno         | 🟢     | v0.16.1 — all tests pass
# aprender       | 🟢     | v0.27.2 — coverage 95%
# realizar       | 🟡     | v0.8.0 — 2 clippy warnings
# whisper-apr    | 🔴     | v0.1.0 — build failure

Signal Levels

Diagnostics Engine

The diagnostics module continuously monitors quality signals:

#![allow(unused)]
fn main() {
// Andon: aggregate signals from all quality sources
pub fn diagnose(workspace: &Workspace) -> HealthReport {
    let mut report = HealthReport::new();

    for component in workspace.components() {
        let signal = match (component.tests_pass(), component.clippy_clean()) {
            (true, true)  => Signal::Green,
            (true, false) => Signal::Yellow,
            (false, _)    => Signal::Red,
        };
        report.add(component.name(), signal);
    }

    report
}
}

Pipeline Andon

Each pipeline phase reports its own Andon signal:

# Pipeline status with timing and errors
batuta status --verbose

# Phase 1: Analysis    🟢  1.2s
# Phase 2: Transpile   🟢  4.1s (depyler)
# Phase 3: Optimize    🟡  2.3s (SIMD fallback: no AVX-512)
# Phase 4: Validate    🔴  FAILED — output mismatch at line 42
# Phase 5: Build       --  Skipped (Jidoka stop)

When Phase 4 signals red, Jidoka halts the pipeline. The Andon board shows exactly where and why.

Benefits

1. Instant awareness - Problems surface immediately, not at release time
2. Root cause focus - Signal includes context, not just pass/fail
3. Team alignment - Everyone sees the same board, same priorities
4. Escalation path - Yellow warns, Red blocks — graduated response

Andon Cord: Manual Signals

Any team member can pull the Andon cord to flag an issue:

# Flag a component for investigation
batuta stack flag realizar --reason "output mismatch on Q4K models"

# Clear after resolution
batuta stack clear realizar

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