5 decks · 130+ cards · SM-2 algorithm

Study smarter.
Remember everything.

BuanCards uses the SM-2 spaced repetition algorithm to show you each card at exactly the right moment — not too soon, not too late. So knowledge moves from short-term to long-term memory.

Start studying How it works

Question

What is the spacing effect?

Answer

Learning is far more effective when practice is spread over time rather than concentrated in a single session — first described by Hermann Ebbinghaus in 1885.

How well did you know it?

Again

Hard

Good

Easy

Why BuanCards

Everything you need to learn deeply

Built around the science of memory — the tools to move knowledge from short-term recall to long-term retention.

Smart Review Scheduling

The SM-2 algorithm calculates exactly when to show each card. Intervals grow longer the better you know it, so you spend time where it matters most.

Two Study Modes

Classic flashcards — reveal and rate. Or switch to quiz mode for multiple-choice practice with explanations. Different sessions call for different approaches.

Capture Notes Mid-Session

Spot a correction or follow-up question while reviewing? Add a study note instantly without losing your flow. Review and action them between sessions.

Rich Markdown Cards

Write cards with full Markdown: code blocks, tables, bold, italic, and more. Perfect for technical subjects where formatting carries meaning.

Retention Analytics

Track your progress deck by deck. See due counts, retention rates, and review history so you always know how your memory is holding up.

Keyboard-First Speed

Press Space to reveal, then rate with one click. No friction between you and the next card.

The library

Five decks. Every card earns its place.

Curated content — not auto-generated. Each card tests a concept that actually comes up in interviews, code reviews, or production incidents.

Senior Software Architect

39 cards

SOLID, CAP/PACELC, DDD, distributed patterns, observability, security, API design, and trade-off reasoning for system design interviews.

Tech Fundamentals: Networking

54 cards

OSI model, TCP/IP, DNS, NAT, TLS, mTLS, subnetting, IP addressing — deep first-principles understanding of how data moves across networks.

Java Date/Time API

14 cards

LocalDate, ZonedDateTime, Instant, Duration, Period, DateTimeFormatter, ChronoUnit, TemporalAdjusters — and how to make time testable with Clock.

Regular Expressions

14 cards

Character classes, quantifiers, anchors, groups, lookahead/lookbehind, Java Pattern/Matcher API, escaping, flags, and performance best practices.

GoF Design Patterns

16 cards

Builder, Factory Method, Singleton, Adapter, Decorator, Facade, Proxy, Composite, Strategy, Observer, Template Method, Command — intent, code, and when NOT to use them.

How it works

Simple to start. Powerful over time.

Build your deck

Create cards with questions and answers. Use Markdown for tables, code blocks, and formatting.

Study your way

Review with classic flashcards or switch to quiz mode for multiple-choice practice with explanations.

Rate your recall

After the answer is revealed, rate yourself: Again, Hard, Good, or Easy. Be honest — the algorithm adapts.

Come back when it counts

SM-2 schedules the next review at the perfect moment — just before you're about to forget.

The science behind it

"With any considerable number of repetitions, a suitable distribution of them over a space of time is decidedly more advantageous than the massing of them at a single time."

— Hermann Ebbinghaus, 1885. The first researcher to systematically study memory and forgetting.

137

flashcards across five curated decks

topic domains from architecture to regex

2–5×

less study time vs traditional methods

SM-2

the algorithm trusted by millions of Anki users

Study smarter. Remember everything.