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No credit cardFree forever planJS · Python · React · DSA · SQL
37,640 XP
28
SD
Tuesday · 24 min studied today

Welcome back, Sam — let's keep the streak alive 🔥

Continue where you left off

Data Structures & Algos · Graphs & Traversals

You're 26% through this track. 5 cards are due for review.

26%
54/210
cards mastered
5
due to review
28
Day streak
keep it going
542
Cards mastered
+12 this week
86%
Quiz accuracy
across 64 quizzes
#214
Global rank
↑ 2 places
+50 XPCard mastered
🔥
28-day streak!personal best
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JSJavaScriptPYPythonReact{ }DSASQLSQLSystem Design
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30Core tracks
Features

Everything you need to actually retain it

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01

Spaced repetition

Rate each card Again / Hard / Good / Easy and adaptive review resurfaces it right before you'd forget — so reviews compound into long-term memory.

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ReactHooksANSWER
Runs once, after the first render — with [] it never re-runs, and cleanup fires on unmount.
02

Build your own decks

Author cards by hand, paste a spreadsheet, or drop in an article and let AI write the flashcards. Tag, color, and study instantly.

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New card · React deck
What does useMemo cache between renders?
The memoized return value of its compute fn
✦ Generate with AI
ReactPerformance
03

Quizzes

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What does the spread in [...arr] produce?
Question 4 / 10★ 3 correct in a row
04

Progress analytics

Accuracy trends, mastery by track, an activity heatmap, and weak-spot drills that target exactly where you're losing points.

See your dashboard
Accuracy by tracklast 30 days
JavaScript
92%
Python
78%
React
85%
DSA
64%
SQL
88%
System
71%
How it works

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1

Pick your tracks

Choose what you're learning — JavaScript, Python, React, DSA, SQL, System Design — and set a daily goal.

2

Study with spaced repetition

Flip cards and rate how well you knew each one. We schedule the next review at the perfect moment.

3

Let AI close the gaps

Quiz yourself, ask the tutor anything, and drill the exact topics where your accuracy is slipping.

Pricing

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Everything you need to build the habit.
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  • Spaced-repetition study & quizzes
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  • Progress tracking & streak history

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