99cards.dev

99cards.dev is a flashcard-based interview preparation system for web developers that uses spaced repetition and active recall to help users master technical concepts and land job offers.

What is 99cards.dev?

99cards.dev is a web-based platform built by web developer Ilyas Seisov. It takes your chosen tech stack area (e.g., React, Node.js, CSS) and produces targeted multiple-choice quizzes with instant feedback and detailed explanations. The system covers 24 technology categories with over 4900 questions, designed to help you understand the "why" behind every answer, not just memorize facts.

Key Features

• Spaced repetition algorithm — Tracks your performance on each concept and schedules reviews just before you'd forget, based on the Ebbinghaus forgetting curve to maximize long-term retention.
• Active recall quizzes — Multiple-choice questions force you to retrieve answers from memory, not passively read, strengthening neural pathways through long-term potentiation.
• 24 technology categories — Frontend (HTML, CSS, JavaScript, TypeScript, React, Angular, Vue), backend (Node.js, Express, Python/Django/Flask, PHP/Laravel, Authentication & Authorization), databases (MySQL, PostgreSQL, MongoDB), full stack (Next.js, Nuxt, REST), Git, and performance optimization.
• Instant feedback and explanations — Every answer shows why it's right or wrong with clear explanations, turning mistakes into learning opportunities.
• Color-coded progress indicators — Completed quizzes show fully correct, partially correct, or all failed at a glance for quick status assessment.
• Granular subtopic selection — Practice specific concepts (e.g., JavaScript closures, React portals) without wasting time on known material.
• Short, focused sessions — Each quiz takes 20–25 minutes, fitting into a lunch break or commute. Research shows spaced repetition can cut study time by 30–40% while improving retention.
• Three interview playbooks included — The Ultimate Web Dev's HR, Technical, and Behavioral Interview Playbooks ($77 value each). First 99 buyers also get the FAANG Interview Playbook ($197 value).

Who is it for?

• Entry-level developers, bootcamp grads, and self-taught coders — Practice the exact concepts that land first jobs, with targeted drills that build foundational knowledge.
• Mid-level developers seeking promotions — Master advanced topics like performance optimization, authentication, and system design to stand out in interviews.
• Senior developers switching tech stacks — Quickly get up to speed on a new framework like Angular or Django using the 20–25 minute daily sessions.
• Developers with interviews in days — Use targeted flashcards to fill last-minute knowledge gaps and reduce anxiety before the real thing.

What can you do with 99cards.dev?

• Prepare for a specific job interview — Select the tech stack from the company's job description and drill the relevant flashcards; track your mastery per category.
• Identify weak areas — Take a quiz in any category; the detailed results show exactly which concepts need more work, allowing you to focus energy where it matters.
• Track progress over time — The dashboard displays skill scores for each technology, so you see measurable improvement and know when you're ready.

How does 99cards.dev work?

1. Choose a technology category and subtopic (e.g., React → Portals).
2. Answer multiple-choice questions using active recall.
3. Get instant feedback with explanations for each answer.
4. The spaced repetition algorithm adjusts review timing based on your accuracy.
5. Repeat daily for 20–25 minutes to lock in knowledge and build rock-solid recall under pressure.

Pricing

Three one-time payment options, no subscriptions:

• Annual — $77 (access to all flashcards + free updates for one year)
• Lifetime — $97 (access to all flashcards + free lifetime updates)
• 7-day trial — $1 (full access for one week)

All plans include the three interview playbooks. First 99 buyers also receive the FAANG Interview Playbook ($197 value). On average, users recoup the investment within 1–2 days of landing a job.

FAQ

Is there a refund guarantee?

Yes. Use the system for 30 days (20–25 minutes/day, 5 days/week) and attend at least one technical interview. If you don't feel dramatic improvement or land a job offer, show proof of effort and get a full refund, plus 3 months free, and keep all bonuses.

Do I need to download an app?

No, it's entirely web-based. You access it through a browser on any device.

How many questions are there?

Over 4900 questions across 24 categories, with new content added periodically.

Are there any hidden fees?

No. The price shown is a one-time payment. There are no recurring subscriptions.

Who created 99cards.dev?

The platform was built by Ilyas Seisov, a web developer who after dozens of failed interviews developed this system to scratch his own itch and eventually landed a dream job with paid relocation.