// Approximate dry material for M20 nominal mix (1 : 1.5 : 3) — for practice only
function mixQuantities(wetVolumeM3) {
  if (!(wetVolumeM3 > 0)) throw new Error("Volume must be a positive number");
  const dryVolume = wetVolumeM3 * 1.54;          // common dry-volume factor
  const parts = 1 + 1.5 + 3;
  const cementM3 = (dryVolume * 1) / parts;
  return {
    cementBags: Math.ceil(cementM3 / 0.0347),    // 50 kg bag ≈ 0.0347 m³
    sandM3: +((dryVolume * 1.5) / parts).toFixed(2),
    aggregateM3: +((dryVolume * 3) / parts).toFixed(2),
  };
}

console.log(mixQuantities(1));
// { cementBags: 9, sandM3: 0.42, aggregateM3: 0.84 }

<label for="vol">Concrete volume (m³)</label>
<input id="vol" type="number" min="0" step="0.1">
<button id="calc">Calculate</button>
<p id="out" aria-live="polite"></p>

<script>
  document.getElementById("calc").addEventListener("click", () => {
    const v = parseFloat(document.getElementById("vol").value);
    try {
      const q = mixQuantities(v);
      document.getElementById("out").textContent =
        `Cement: ${q.cementBags} bags, Sand: ${q.sandM3} m³, Aggregate: ${q.aggregateM3} m³`;
    } catch (e) {
      document.getElementById("out").textContent = e.message;
    }
  });
</script>

import { useState } from "react";

export default function InspectionForm({ onSaved }) {
  const [site, setSite] = useState("");
  const [item, setItem] = useState("Shuttering");
  const [ok, setOk] = useState(true);
  const [error, setError] = useState("");

  async function submit(e) {
    e.preventDefault();
    const res = await fetch("/api/inspections", {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ site, item, ok }),
    });
    if (!res.ok) return setError((await res.json()).error);
    setError("");
    onSaved(await res.json());
  }

  return (
    <form onSubmit={submit}>
      <input value={site} onChange={(e) => setSite(e.target.value)} placeholder="Site name" />
      <select value={item} onChange={(e) => setItem(e.target.value)}>
        <option>Shuttering</option><option>Reinforcement</option><option>Curing</option>
      </select>
      <label><input type="checkbox" checked={ok} onChange={(e) => setOk(e.target.checked)} /> Passed</label>
      <button type="submit">Save</button>
      {error && <p role="alert">{error}</p>}
    </form>
  );
}

// npm install express mongoose
const express = require("express");
const mongoose = require("mongoose");

const Inspection = mongoose.model("Inspection", new mongoose.Schema({
  site: { type: String, required: true, trim: true },
  item: { type: String, enum: ["Shuttering", "Reinforcement", "Curing"], required: true },
  ok: { type: Boolean, default: true },
}, { timestamps: true }));

const app = express();
app.use(express.json());

app.post("/api/inspections", async (req, res) => {
  try {
    const doc = await Inspection.create(req.body);
    res.status(201).json(doc);
  } catch (err) {
    res.status(400).json({ error: err.message });
  }
});

app.get("/api/inspections", async (req, res) => {
  res.json(await Inspection.find().sort({ createdAt: -1 }).limit(50));
});

mongoose.connect(process.env.MONGO_URL || "mongodb://localhost:27017/sitebook")
  .then(() => app.listen(4000, () => console.log("API on 4000")));

// Explain the output, then fix the bug
for (var i = 0; i < 3; i++) {
  setTimeout(() => console.log(i), 0);
}
// Prints 3, 3, 3 — var is function-scoped, so callbacks share one i

for (let j = 0; j < 3; j++) {
  setTimeout(() => console.log(j), 0);
}
// Prints 0, 1, 2 — let creates a new binding for each iteration

Two-minute pitch
"I trained and worked as a civil engineer, where I planned work,
estimated quantities and checked quality against standards.
I moved into software deliberately and spent the last months building
MERN applications — my main project is a site inspection tracker
with a React frontend, an Express API and MongoDB, deployed at ____.
I bring careful planning and domain understanding, and I am looking for
a junior full stack role, ideally where engineering knowledge helps."

Phase 1 (months 1-3): HTML, CSS, JavaScript, Git — calculator + reference page
Phase 2 (months 4-5): React — inspection checklist UI
Phase 3 (months 6-8): Node, Express, MongoDB, auth — full tracker app
Phase 4 (months 9+):  Deploy, tests, README, interview prep, applications

Week __  Phase __
Hours studied: ____
Concepts learned: ____
Code pushed (links): ____
Stuck on: ____  How I solved it: ____
Next week: ____

Company type                  | Why my background helps | Names to research
Construction tech             | I know site workflows   | ____
Real estate / property apps   | Project and cost data   | ____
Engineering software          | Domain vocabulary       | ____
General product / services    | Strong MERN projects    | ____