Pattern before syntax
Visual reasoning and plain-English invariants come before the editor.
cccrabcode
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The guided Rust learning platform
Think clearly.
Code fearlessly in Rust.
Learn the complete Rust language from first principles, then master 150 interview problems through real execution, progressive hints, and idiomatic explanations.
28 Rust course units150 algorithm lessonsReal Rust execution
LIVE RUST WORKSPACE
FEATURED LESSON
EasyTwo Sum
Arrays & Hashing→Guided Rust→Mastery
solution.rsRUST
1 pub fn solve(input: &[i32]) -> Answer 2 { 3 // name the invariant 4 todo!() 5 } 6
Lesson 3 of 9Guided Rust path
◆
Why this lesson Build a strong Rust problem-solving foundation with guided reasoning.
03progressive hints✓private testsO(n)analysis
NEW · THE COMPLETE LANGUAGE TRACKThe Rust Book,
The Rust Book,
rebuilt for active learning.
Twenty-one chapters and seven appendices become an interactive Rustbook: 87 focused section guides with predictions, saved workpads, confidence checks, annotated reveals, compiler repair, runnable labs, projects, and spaced review.
01FoundationsTooling · syntax · ownership · types
→02Building programsErrors · tests · Cargo · projects
→03Systems RustPointers · threads · async · traits
→04MasteryPatterns · unsafe · macros · server
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YOUR ROADMAP
0 of 150 solved
A little Rust, every day.
0Problems solved
0Patterns learned
0Experience points
0Day streak
ADAPTIVE PRACTICE
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The Crabcode 150
Your path from arrays
to advanced graphs.
Based on the NeetCode 150, rebuilt as a guided Rust curriculum. Choose a pattern, then work through its problems in order.
SolvedIn progressUp next
Pattern mapFollow the branches from foundations to advanced techniques.SELECTEDArrays & Hashing
WHY RUST?Learn the algorithm.
Learn the algorithm.
Understand the machine.
Crabcode turns Rust’s strictness into a teaching tool. Every lesson calls out the ownership, borrowing, and type decisions that make your solution safe and fast.
LEARN
Hints, not spoilers
Three progressive nudges preserve the breakthrough while keeping you moving.
Idiomatic Rust
Every solution explains ownership choices, correctness, and complexity.
Execution with feedback
Run real Rust, add your own tests, and turn failures into targeted coaching.