Self-directed project
Frontend Engineering with Prediction Game
Junior Front-End Engineer · Software Engineering · July 2026
Built a complete World Cup prediction game end to end: rendered the fixture board, scored picks with the exact 5/2/0 rules, derived team attack strengths from real results, and used them in a bot predictor that auto-picks every match. Also deployed the finished experience to a live https Netlify URL for immediate sharing.
Graded against
- Scoring engine correctness30%
- Prediction model genuinely from real data25%
- Game completeness and leaderboard soundness25%
- Shipped and shareable: live deployed URL20%
Passed · pass mark 60/100
What stood out6
- Implemented the exact scoring rubric, including correct handling of draws and exact-score matches.
- Computed team strengths from a real-results sample and used those strengths inside the bot prediction logic.
- Shipped a live Netlify deployment URL that matches the project’s shareable-delivery requirement.
- Leakage-Free Feature Engineering
- Honest Model Evaluation
- End-to-End Game Assembly
The work I submitted10 tasks
Lab Orientation
{"code":"<!DOCTYPE html>\n<html lang=\"en\">\n <head>\n <meta charset=\"UTF-8\" />\n <title>Predict the Cup</title>\n <style>\n body {\n font-family: -apple-system, sans-serif;\n background: #FDFCF7;\n color: #0E1726;\n padding: 32px;\n margin: 0;\n }\n h1 {\n color: #00C65A;\n font-size: 32px;\n margin: 0 0 12px 0;\n }\n p {\n color: #3F4B5F;\n margin: 0;\n }\n </style>\n </head>\n <body>\n <h1>Param's Prediction Game</h1>\n <p>Welcome to your prediction game.</p>\n </body>\n</html>","ranAt":"2026-07-26T13:51:41.990Z"}Example Render Fixtures
{"code":"<!DOCTYPE html>\n<html>\n<head>\n <meta charset=\"utf-8\" />\n <title>Worked Example - Render Two Matches</title>\n\n <style>\n body {\n font: 15px/1.4 system-ui;\n padding: 24px;\n background: #F7F8FA;\n }\n\n h1 {\n color: #0E1726;\n }\n\n .match {\n background: #fff;\n border: 1px solid #E4E8EE;\n border-radius: 12px;\n padding: 14px;\n margin-bottom: 12px;\n max-width: 360px;\n }\n\n .teams {\n font-weight: 800;\n color: #0E1726;\n margin-bottom: 8px;\n }\n\n .picks {\n display: grid;\n grid-template-columns: 1fr auto 1fr;\n gap: 8px;\n align-items: center;\n }\n\n input {\n padding: 8px;\n border: 1px solid #E4E8EE;\n border-radius: 8px;\n text-align: center;\n font-size: 16px;\n }\n\n .vs {\n color: #6A7589;\n font-weight: 700;\n font-size: 12px;\n }\n </style>\n</head>\n\n<body>\n\n <h1>My Picks</h1>\n\n <div id=\"board\"></div>\n\n <script>\n\n // Sample match data\n const SAMPLE_FIXTURES = [\n {\n home: \"Germany\",\n away: \"Brazil\",\n date: \"2026-06-28\"\n },\n {\n home: \"France\",\n away: \"Spain\",\n date: \"2026-06-29\"\n }\n ];\n\n // Get the board\n const board = document.getElementById(\"board\");\n\n // Create one card for each match\n SAMPLE_FIXTURES.forEach((match) => {\n\n const card = document.createElement(\"div\");\n card.className = \"match\";\n\n card.setAttribute(\n \"data-match\",\n match.home + \"-\" + match.away\n );\n\n card.innerHTML =\n '<div class=\"teams\">' +\n match.home +\n ' vs ' +\n match.away +\n '</div>' +\n\n '<div class=\"picks\">' +\n '<input type=\"number\" min=\"0\" placeholder=\"0\">' +\n '<span class=\"vs\">vs</span>' +\n '<input type=\"number\" min=\"0\" placeholder=\"0\">' +\n '</div>';\n\n board.appendChild(card);\n\n });\n\n </script>\n\n</body>\n</html>","ranAt":"2026-07-26T13:53:45.072Z"}Act1 Fixtures Form
{"code":"<!doctype html>\n<html>\n<head>\n <meta charset=\"utf-8\" />\n <title>Predict the Cup · my picks</title>\n\n <style>\n body {\n font: 15px/1.45 system-ui, -apple-system, \"Segoe UI\", sans-serif;\n padding: 24px;\n background: #F7F8FA;\n color: #0E1726;\n }\n\n h1 {\n margin: 0 0 4px;\n font-size: 22px;\n }\n\n .sub {\n color: #6A7589;\n font-size: 13px;\n margin-bottom: 16px;\n }\n\n #board {\n display: grid;\n gap: 12px;\n max-width: 640px;\n }\n\n .match {\n background: #fff;\n border: 1px solid #E4E8EE;\n border-radius: 12px;\n padding: 14px;\n }\n\n .meta {\n color: #6A7589;\n font-size: 11px;\n text-transform: uppercase;\n letter-spacing: 0.14em;\n margin-bottom: 6px;\n }\n\n .teams {\n font-weight: 800;\n font-size: 15.5px;\n margin-bottom: 8px;\n }\n\n .picks {\n display: grid;\n grid-template-columns: 1fr auto 1fr;\n gap: 8px;\n align-items: center;\n }\n\n .picks input {\n padding: 9px;\n border: 1px solid #E4E8EE;\n border-radius: 8px;\n text-align: center;\n font: inherit;\n font-weight: 700;\n font-size: 15px;\n }\n\n .vs {\n color: #6A7589;\n font-weight: 700;\n font-size: 12px;\n }\n\n footer {\n color: #6A7589;\n font-size: 11px;\n margin-top: 24px;\n max-width: 640px;\n line-height: 1.5;\n }\n </style>\n</head>\n\n<body>\n\n <h1>My picks</h1>\n <div class=\"sub\">2026 World Cup · Round of 32</div>\n\n <div id=\"board\"></div>\n\n <footer>\n Independent learning project. Not affiliated with or endorsed by FIFA.\n Fixtures snapshot: openfootball/worldcup.json (CC0-1.0).\n </footer>\n\n <script>\n const FIXTURES = [\n { home: \"Germany\", away: \"Mexico\", date: \"2026-06-28\", round: \"R32\" },\n { home: \"Argentina\", away: \"Switzerland\", date: \"2026-06-29\", round: \"R32\" },\n { home: \"France\", away: \"Portugal\", date: \"2026-06-30\", round: \"R32\" },\n { home: \"Spain\", away: \"Uruguay\", date: \"2026-07-01\", round: \"R32\" },\n { home: \"Brazil\", away: \"Japan\", date: \"2026-07-02\", round: \"R32\" },\n { home: \"England\", away: \"Netherlands\", date: \"2026-07-03\", round: \"R32\" },\n ];\n\n function renderFixtures() {\n const board = document.getElementById(\"board\");\n\n board.innerHTML = \"\";\n\n FIXTURES.forEach((match) => {\n\n const card = document.createElement(\"div\");\n card.className = \"match\";\n card.setAttribute(\"data-match\", match.home + \"-\" + match.away);\n\n card.innerHTML = `\n <div class=\"meta\">${match.round} · ${match.date}</div>\n\n <div class=\"teams\">\n ${match.home} vs ${match.away}\n </div>\n\n <div class=\"picks\">\n <input type=\"number\" min=\"0\" placeholder=\"-\">\n\n <span class=\"vs\">VS</span>\n\n <input type=\"number\" min=\"0\" placeholder=\"-\">\n </div>\n `;\n\n board.appendChild(card);\n\n });\n }\n\n renderFixtures();\n </script>\n\n</body>\n</html>","selfCheck":{"cases":[{"name":"FIXTURES const is in scope","pass":true,"detail":""},{"name":"One card per fixture (data-match)","pass":true,"detail":""},{"name":"Two number inputs per card","pass":true,"detail":""},{"name":"Team names visible on each card","pass":true,"detail":""}],"ranAt":"2026-07-26T13:57:48.911Z"},"ranAt":"2026-07-26T13:57:48.911Z"}Act2 Scoring Function
{"code":"<!doctype html>\n<html lang=\"en\">\n <head>\n <meta charset=\"utf-8\">\n <title>scorePick · your turn</title>\n </head>\n <body>\n <h1>scorePick · your turn</h1>\n\n <pre id=\"out\" style=\"font-family:ui-monospace,Menlo,monospace;font-size:13px;white-space:pre-wrap\"></pre>\n\n <script>\n // ─────────────────────────────────────────────────────────────────────\n // scorePick()\n // exact score -> 5\n // right result, wrong score -> 2\n // wrong result -> 0\n // ─────────────────────────────────────────────────────────────────────\n\n function scorePick(predicted, actual) {\n\n // Exact score\n if (\n predicted.home === actual.home &&\n predicted.away === actual.away\n ) {\n return 5;\n }\n\n // Determine predicted result\n let predictedResult;\n if (predicted.home > predicted.away) {\n predictedResult = \"home\";\n } else if (predicted.home < predicted.away) {\n predictedResult = \"away\";\n } else {\n predictedResult = \"draw\";\n }\n\n // Determine actual result\n let actualResult;\n if (actual.home > actual.away) {\n actualResult = \"home\";\n } else if (actual.home < actual.away) {\n actualResult = \"away\";\n } else {\n actualResult = \"draw\";\n }\n\n // Same result but different score\n if (predictedResult === actualResult) {\n return 2;\n }\n\n // Wrong result\n return 0;\n }\n\n // Local sanity-check\n const cases = [\n { pred: { home: 2, away: 1 }, actual: { home: 2, away: 1 }, why: \"exact 2-1\" },\n { pred: { home: 3, away: 0 }, actual: { home: 1, away: 0 }, why: \"home win, wrong score\" },\n { pred: { home: 0, away: 1 }, actual: { home: 2, away: 0 }, why: \"wrong result\" },\n { pred: { home: 1, away: 1 }, actual: { home: 2, away: 2 }, why: \"both draws\" },\n ];\n\n const out = document.getElementById(\"out\");\n\n out.textContent = cases\n .map(\n c =>\n `${c.pred.home}-${c.pred.away} vs ${c.actual.home}-${c.actual.away} -> ${scorePick(c.pred, c.actual)} // ${c.why}`\n )\n .join(\"\\n\");\n </script>\n </body>\n</html>","ranAt":"2026-07-26T14:00:29.759Z","passed":true,"attempt":1,"selfCheck":{"cases":[{"name":"exact 2-1 vs 2-1 returns 5","pass":true},{"name":"home win 3-0 vs 1-0 returns 2","pass":true},{"name":"wrong result 0-1 vs 2-0 returns 0","pass":true},{"name":"draw 1-1 vs 2-2 returns 2","pass":true}],"ranAt":"2026-07-26T14:00:29.759Z"}}Example Compute Strengths
{"code":"<!doctype html>\n<html>\n<head><meta charset=\"utf-8\"><title>Worked example · computeStrengths</title></head>\n<body>\n\n<script>\n// ── A tiny sample ────────────────────────────────────────────────────────────\n// (same SHAPE as your real results; different teams + numbers on purpose).\nconst SAMPLE = [\n { home: 'Japan', away: 'Senegal', homeScore: 2, awayScore: 1 },\n { home: 'Morocco', away: 'Japan', homeScore: 0, awayScore: 2 },\n { home: 'Senegal', away: 'Morocco', homeScore: 1, awayScore: 1 },\n];\n\n// ── computeStrengths ─────────────────────────────────────────────────────────\n// Two numbers per team: ATTACK = avg goals scored, DEFENSE = avg goals conceded.\nfunction computeStrengths(matches) {\n // Step 1 — a running tally for every team: scored, conceded, games.\n const tally = {};\n const seed = (t) => { if (!tally[t]) tally[t] = { scored: 0, conceded: 0, games: 0 }; };\n\n // Step 2 — every row touches BOTH teams. Home and away are mirror images.\n for (const m of matches) {\n seed(m.home); seed(m.away);\n // home team: SCORED its own goals, CONCEDED the away goals.\n tally[m.home].scored += m.homeScore;\n tally[m.home].conceded += m.awayScore;\n tally[m.home].games += 1;\n // away team: the other way round.\n tally[m.away].scored += m.awayScore;\n tally[m.away].conceded += m.homeScore;\n tally[m.away].games += 1;\n }\n\n // Step 3 — divide each total by games to get the two averages.\n const table = {};\n for (const team of Object.keys(tally)) {\n const r = tally[team];\n table[team] = { attack: r.scored / r.games, defense: r.conceded / r.games };\n }\n return table;\n}\n\n// ── The result ───────────────────────────────────────────────────────────────\nconst strengths = computeStrengths(SAMPLE);\nconsole.log(strengths.Japan); // → { attack: 2, defense: 0.5 }\n</script>\n\n</body>\n</html>\n","ranAt":"2026-07-26T14:01:12.735Z"}Act3 Compute Strength
{"passed":true,"attempt":1,"selfCheck":{"allPass":true,"failedNames":[]},"ranAt":"2026-07-26T14:04:07.867Z"}Act3 House Bot
{"passed":true,"attempt":1,"selfCheck":{"allPass":true,"failedNames":[]},"ranAt":"2026-07-26T14:07:48.048Z"}Act4 Leaderboard
{"ranAt":"2026-07-26T14:10:40.963Z","passed":false,"attempt":1}Act5 Assemble
{"code":"<!doctype html>\n<html lang=\"en\">\n<head>\n<meta charset=\"utf-8\" />\n<meta name=\"viewport\" content=\"width=device-width, initial-scale=1\" />\n<title>Predict the Cup — my World Cup prediction game</title>\n<style>\n :root { --green:#00C65A; --ink:#0E1726; --soft:#3F4B5F; --faint:#6A7589; --line:#E4E8EE; --paper:#fff; --bg:#F4F7F6; }\n * { box-sizing: border-box; }\n body { font-family: ui-sans-serif, system-ui, -apple-system, \"Segoe UI\", sans-serif;\n margin:0; background:var(--bg); color:var(--ink); }\n .wrap { max-width: 760px; margin: 0 auto; padding: 22px 18px 40px; }\n header { display:flex; align-items:center; gap:12px; margin-bottom:6px; }\n .badge { width:42px; height:42px; border-radius:12px; background:var(--green); color:#fff;\n display:flex; align-items:center; justify-content:center; font-weight:900; font-size:18px; }\n h1 { font-size:21px; margin:0; letter-spacing:-0.01em; }\n .tag { color:var(--faint); font-size:13px; margin:2px 0 18px; }\n h2 { font-size:13px; text-transform:uppercase; letter-spacing:0.12em; color:var(--faint); margin:24px 0 12px; }\n #board { display:grid; grid-template-columns:1fr; gap:12px; }\n @media (min-width:560px){ #board { grid-template-columns:1fr 1fr; } }\n .match { background:var(--paper); border:1px solid var(--line); border-radius:14px; padding:14px; }\n .meta { color:var(--faint); font-size:10.5px; text-transform:uppercase; letter-spacing:0.12em; margin-bottom:8px; }\n .teams { display:grid; grid-template-columns:1fr auto 1fr; align-items:center; gap:8px; font-weight:800; font-size:15px; }\n .teams .vs { color:var(--faint); font-weight:700; font-size:11px; }\n .teams .away { text-align:right; }\n .picks { display:grid; grid-template-columns:1fr auto 1fr; align-items:center; gap:8px; margin-top:10px; }\n .picks input { padding:10px; border:1px solid var(--line); border-radius:9px; text-align:center;\n font:inherit; font-weight:800; font-size:16px; width:100%; }\n .picks input:focus { outline:2px solid var(--green); border-color:var(--green); }\n .picks .dash { color:var(--faint); font-weight:800; text-align:center; }\n .botline { margin-top:10px; font-size:12px; color:var(--soft); }\n .botline b { color:var(--ink); font-variant-numeric:tabular-nums; }\n .botline .prob { color:var(--faint); font-weight:600; }\n .hint { color:var(--faint); font-size:12px; line-height:1.5; margin:8px 0 2px; max-width:560px; }\n .challenge-banner { background:rgba(0,198,90,0.10); border:1px solid var(--green); border-radius:12px; padding:12px 14px; font-size:14px; font-weight:700; color:var(--ink); margin:14px 0 4px; }\n .vs-friend { font-size:15px; font-weight:800; color:var(--green); margin-top:12px; }\n .share-row { display:flex; gap:8px; flex-wrap:wrap; align-items:center; margin-top:14px; }\n .namebox { flex:1; min-width:150px; padding:11px 12px; border:1px solid var(--line); border-radius:10px; font:inherit; }\n .namebox:focus { outline:2px solid var(--green); border-color:var(--green); }\n .sharebtn { font:inherit; font-weight:800; color:#fff; background:var(--ink); border:0; border-radius:999px; padding:11px 18px; cursor:pointer; }\n .sharebtn:hover { filter:brightness(1.15); }\n .shareurl { width:100%; margin-top:8px; padding:9px 11px; border:1px solid var(--line); border-radius:8px; font-family:ui-monospace,Menlo,monospace; font-size:12px; color:var(--soft); }\n .proov-credit { margin-top:12px; font-size:11.5px; }\n .proov-credit a { color:var(--green); font-weight:800; text-decoration:none; }\n .result { margin-top:10px; font-size:12px; font-weight:700; color:var(--green);\n border-top:1px dashed var(--line); padding-top:9px; }\n .scorebtn { margin-top:18px; font:inherit; font-weight:800; font-size:15px; color:#fff;\n background:var(--green); border:0; border-radius:999px; padding:13px 22px; cursor:pointer; width:100%; }\n @media (min-width:560px){ .scorebtn { width:auto; } }\n .
…Final Submission
{"url":"https://6a661cd1e57afd605733442c--tranquil-profiterole-f9d3a3.netlify.app","submittedAt":"2026-07-26T14:45:28.995Z"}