rustlings¶

Level: 101 · for newcomers

One line: rustlings ↗ is ~100 small files that do not compile, and your job is the smallest change that makes each one work — which makes the compiler the teacher, in doses small enough that a red error is a puzzle rather than a wall.

Why it is foundational¶

Because reading about ownership and writing code that owns something are different skills, and only one of them is what you actually wanted.

The specific thing rustlings does that neither The Book nor Rust by Example can: it puts you in front of a compiler error you have to resolve, roughly a hundred times, early. That is the loop you will be in for your whole Rust career, and the sooner error[E0382]: borrow of moved value stops reading as a rejection and starts reading as information, the sooner Rust becomes pleasant.

It is also under rust-lang/ — official, maintained, 35k stars — and its own README recommends running it in parallel with The Book, which is the pairing this section is built around.

Installing it¶

cargo install rustlings
rustlings init
cd rustlings
rustlings

Bare rustlings starts the interactive watcher: it opens the next unsolved exercise, recompiles on save, and moves you on when it passes.

The curl … install.sh | bash line you may have seen is dead. That installer was removed; the URL now 404s. cargo install rustlings is the current method — verified here against rustlings 6.5.0, whose subcommands are:

Command	Does
`rustlings`	the watcher — next pending exercise, recompiling as you save
`rustlings run <name>`	run one exercise
`rustlings hint`	a hint for the current one
`rustlings check-all`	mark everything done or pending
`rustlings reset <name>`	put an exercise back how it started

hint is the one to know about. Use it — a stuck exercise teaches nothing, and the hints are written to nudge rather than solve.

Which exercise goes with which chapter¶

The 24 exercise sets, in rustlings' own order, against the Book chapter that prepares you for each — and, in the third column, the page here that goes deeper when one of them will not click.

Chapter names are given as well as numbers on purpose: the numbering changed with the 2024 edition, so any older mapping you find (including ones that cite "§18.3" for patterns) points at the wrong chapter now.

rustlings	The Book	Deeper, here
`00_intro`	ch1 Getting Started	Running a scratch program
`01_variables`	ch3.1 Variables and Mutability	Initial values · A name is not a place
`02_functions`	ch3.3 Functions	A block is an expression
`03_if`	ch3.5 Control Flow	A block is an expression
`04_primitive_types`	ch3.2 Data Types · ch4.3 The Slice Type	Six kinds of zero · What a float stores
`05_vecs`	ch8.1 Vectors	`Option` is a one-item collection
`06_move_semantics`	ch4.1 What Is Ownership? · ch4.2 References and Borrowing	Ownership and moves · Borrowing
`07_structs`	ch5.1 Defining Structs · ch5.3 Methods	Representing a record · The newtype
`08_enums`	ch6 Enums and Pattern Matching · ch19 Patterns and Matching	`if let` · `while let`
`09_strings`	ch8.2 Strings	Meet the byte
`10_modules`	ch7 Packages, Crates, and Modules	Scope is about names
`11_hashmaps`	ch8.3 Hash Maps	—
`12_options`	ch6.1 Defining an Enum	OPTION.md — the whole map
`13_error_handling`	ch9 Error Handling	`Option` vs `Result` · `unwrap` is a TODO
`14_generics`	ch10.1 Generic Data Types	`Result` aliases
`15_traits`	ch10.2 Traits	`Debug` and `Display`
`16_lifetimes`	ch10.3 Lifetimes	Borrowing
`17_tests`	ch11 Writing Automated Tests	cargo-nextest
`18_iterators`	ch13.1 Closures · ch13.2 Iterators	`Option` is a one-item collection
`19_smart_pointers`	ch15 Smart Pointers	Nullable pointers
`20_threads`	ch16 Fearless Concurrency	Mutex poisoning
`21_macros`	ch20 Advanced Features	The braces take a name
`22_clippy`	(no chapter — tooling)	Strict clippy lints
`23_conversions`	ch10.2 Traits (`From` / `Into`)	`Option` vs `Result`

There is also a quizzes set, interleaved between the others, which combines several topics at once — those are the ones worth slowing down on, because a quiz you cannot do names the chapter you skimmed.

Where it stops¶

By around exercise 60 you are fixing other people's nearly-correct programs, which is a genuine skill and not the one you eventually need. Nothing in rustlings asks you to design a type, choose between two valid approaches, or decide what your program should do when input is bad — because every exercise has exactly one intended answer.

So finish it, or do not; either is fine. But when it starts feeling like filling in blanks, that is the signal to move to something with an open answer: 100 Exercises to Learn Rust, the katas here, or a program of your own in the practice tree.

If you are coming from another language¶

Python — closest to a test-driven kata site, except the failing thing is the compiler rather than an assertion, which is the adjustment. In Python a program that is wrong still runs; here it does not build, and learning to read that as help rather than obstruction is most of what rustlings is for.
ABAP — the nearest feeling is a syntax check that refuses activation, which you already know how to work with. The difference in degree is large: Rust's checks cover ownership and lifetimes, so the compiler objects to things that would have been runtime bugs elsewhere.

Po polsku¶

Warto nazwać wprost, czego rustlings uczy naprawdę, bo dla uczącego się po polsku to nie do końca to samo, co dla Amerykanina: umiejętności czytania komunikatów rustc. Kompilator odzywa się wyłącznie po angielsku i nic tego nie zmieni — nie ma polskiej wersji diagnostyki, rustlings hint też jest po angielsku. Dobra wiadomość jest taka, że to język zamknięty: kilkadziesiąt powtarzalnych formuł, które po dwudziestym ćwiczeniu rozpoznaje się z jednego rzutu oka (borrow of moved value, expected …, found …, does not live long enough). Stąd jedna konkretna rada na start: czytaj cały komunikat, nie samą czerwoną linijkę. Rozwiązanie stoi zwykle niżej, w wierszach help: i note:, i to właśnie te wiersze polski czytelnik odruchowo pomija jako „resztę tekstu po angielsku”.

Instalacja to miejsce, w którym polskojęzyczne poradniki starzeją się najszybciej. Krążąca po blogach i materiałach kursowych linijka curl … install.sh | bash już nie działa — instalator usunięto, adres zwraca 404. Aktualna droga to cargo install rustlings, potem rustlings init, a samo rustlings uruchamia tryb czuwania. Tabela poleceń na tej stronie odpowiada wersji 6.5.0, więc jeśli znaleziony poradnik pokazuje inne polecenia niż te, jest po prostu starszy od narzędzia — sprawdź rustlings --help, zanim uznasz, że coś jest zepsute u ciebie.

Na koniec granica, o której mówi sekcja Where it stops, po polsku dotyczy czegoś jeszcze. Około sześćdziesiątego ćwiczenia poprawiasz cudze, prawie gotowe programy — a ćwiczenie z luką do wypełnienia nigdy nie każe ci niczego nazwać: ani typu, ani funkcji, ani modułu. Nazywanie jest dokładnie tą częścią, w której obcy język zaczyna kosztować, więc odkładanie własnego programu na później oznacza odkładanie jedynego ćwiczenia, które ten koszt oswaja. Kiedy rustlings zacznie przypominać wypełnianie formularza, to jest sygnał, żeby napisać coś swojego.

Szukaj po polsku: ćwiczenia z Rusta · jak czytać komunikaty kompilatora Rust · cargo install rustlings · rustlings hint · rust error index E0382