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Fabio Ritzel Borges
Fabio Ritzel Borges

Posted on Originally published at flabs.tech

DevSprint — JavaScript Quiz Mini-Game

What is DevSprint?

DevSprint is an arcade-style JavaScript quiz that tests the topics commonly asked in technical interviews. Built as a portfolio feature on flabs.tech, it's a fast, tense sprint through 20 questions — 20 seconds each, 3 lives, streak multipliers.

How it works

  • 20 of 44 questions sampled per run from a bank covering closures, event loop, type coercion, data structures, algorithms, and gotchas
  • 20-second timer with SVG countdown ring — correct answers earn a 2-second bonus
  • Streak multiplier up to x5 — build momentum for massive scores
  • 3 lives — wrong answer or timeout costs one; game over at zero

Features

Leaderboard

Scores are persisted to Redis via Upstash with weekly and all-time sorted sets. The top 10 are shown on the start card and game-over screen with gold/silver/bronze badges.

Achievements

Unlock achievements for milestones: First Blood, Perfect 20, Speed Demon, Comeback, and Sharpshooter. All stored in localStorage — no server needed.

Referral Opportunities

Score 80% or higher and you'll see a referral card for opportunities. The URL is configurable via environment variable.

Shareable Result Cards

Save your score and get a unique result page with an OG image card — perfect for sharing on social media.

Printable Certificate

The result page includes a printable completion certificate with your score, accuracy, and rank.

Daily challenge

A deterministic daily challenge picks one question from the bank — check back every day for a new one.

Tech stack

  • Next.js 16 App Router + TypeScript
  • Mantine v9 components + SCSS Modules
  • Upstash Redis for leaderboard persistence
  • PostHog analytics (consent-gated)
  • Playwright E2E tests + Vitest unit tests

Try it

Head to flabs.tech/quiz and test your JavaScript fundamentals. Can you reach Staff rank?

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