rxdt · rxdt · Jul 18, 2026 · Jul 14, 2026
diff --git a/harness/js-scaffold/PROMPT.md b/harness/js-scaffold/PROMPT.md
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+# JS Quiz Scaffold
+
+A minimal vanilla JS quiz that checks answers and colors buttons.
+
+## Rules
+- Do not change the correct answer without updating specs/quiz.md
+- Tests must pass after every change: `npm test`
+- Do not add frameworks or large dependencies
diff --git a/harness/js-scaffold/README.md b/harness/js-scaffold/README.md
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+# JS Scaffold Example
+
+Shows how Ralph works with a frontend JS project.
+
+## Structure
+- `PROMPT.md` — rules Ralph must follow
+- `specs/` — behavior specs Ralph must not break
+- `npm test` — fails if behavior is broken
+
+## Usage
+npm install
+npm test
diff --git a/harness/js-scaffold/index.html b/harness/js-scaffold/index.html
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+<!DOCTYPE html>
+<html lang="en">
+
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Quiz</title>
+    <script src="./quiz.js" type="module" defer></script>
+    <style>
+        body {
+    display: flex;
+    flex-direction: column;
+    justify-content: center; 
+    align-items: center;          
+    margin: 0;
+}
+h1{
+    font-size: 3.4rem;
+}
+p{
+    font-size: 1.5rem;
+   text-align: center
+}
+button{
+    padding-inline: 1.5rem;
+    width: 100%;
+    font-size: 1rem;
+    padding-block: 0.5rem;
+    display: block;
+    margin-bottom: 1rem;
+}
+    </style>
+</head>
+<body>
+    <main>
+        <header>
+            <h1> Quiz Test </h1>
+        </header>
+        <section>
+            <p>NaN === NaN</p>
+            <button id="btn-true" type="button">True</button>
+            <button id="btn-false" type="button">False</button>
+        </section>
+    </main>
+</body>
+
+</html>
diff --git a/harness/js-scaffold/package.json b/harness/js-scaffold/package.json
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+{
+    "name": "js-scaffold" ,
+    "type": "module" ,
+    "scripts": {
+        "test": "node --test test.js"
+    }
+
+}
diff --git a/harness/js-scaffold/quiz.js b/harness/js-scaffold/quiz.js
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+export function checkAnswer(answer){
+const correctAnswer = false;
+return answer===correctAnswer
+}
+function testQuiz(){
+    const trueBtn=document.getElementById('btn-true');
+    const falseBtn=document.getElementById('btn-false');
+    trueBtn.addEventListener('click',()=>{
+const isCorrect = checkAnswer(true);
+trueBtn.style.background = isCorrect ? '#d4edda' : '#f8d7da';
+falseBtn.style.background=''
+    })
+    falseBtn.addEventListener('click',()=>{
+const isCorrect = checkAnswer(false);
+falseBtn.style.background = isCorrect ? '#d4edda' : '#f8d7da';
+trueBtn.style.background=''
+    })
+}
+    if(typeof document!=='undefined'){
+        testQuiz()
+    }
diff --git a/harness/js-scaffold/specs/quiz.md b/harness/js-scaffold/specs/quiz.md
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+# Quiz Specs
+
+## checkAnswer(answer)
+- returns true when answer matches the correct answer
+- returns false otherwise
+- correct answer for "NaN === NaN" is false
diff --git a/harness/js-scaffold/test.js b/harness/js-scaffold/test.js
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+import test from 'node:test';
+import assert from 'node:assert';
+import { checkAnswer } from './quiz.js';
+test(' Quiz - checkAnswer function',()=>{
+    assert.strictEqual( checkAnswer(false) , true );
+    assert.strictEqual(checkAnswer(true) , false)
+})
+