Crystal
Full course · 21 lessonsCrystal is a statically typed, compiled language with Ruby-like syntax but blazing performance via LLVM. It excels at web applications, backend services, and systems programming with type inference and nil safety.
Getting Started with Crystal
Install, compile, and run Crystal.
Variables and Types
Type inference, unions, and constants.
Control Flow
if, unless, case, and loops.
Strings and Interpolation
String ops, interpolation, and heredocs.
Arrays and Tuples
Collections and tuple types.
Hashes and Sets
Key-value storage.
Methods
Define methods with args and returns.
Classes
OOP with classes and accessors.
Modules and Mixins
Code reuse with modules.
Enums
Typed enumerations.
Exceptions
Raise and rescue errors.
Blocks and Procs
Higher-order functions.
File and Standard IO
Read and write files.
Generics
Type-parameterized code.
Fibers and Channels
Green threads and CSP.
Macros
Compile-time metaprogramming.
Web Servers with Kemal
Build HTTP services.
HTTP Clients and JSON
Consume APIs from Crystal.
Database Access
SQLite and Postgres with Crystal.
Testing with Spec
Unit and integration tests.
Ecosystem and Next Steps
Shards, community, and production use.