G1Joshi Crystal
Crystal compiles to native code (using LLVM) but looks exactly like Ruby. v1.12 continues improving Windows support and parallelism.
When to Use
- Performance sensitive Rubyists: Porting heavy Ruby scripts to Crystal for 50x speedup.
- Microservices: Low memory footprint compared to JVM/Ruby.
- CLI Tools: Fast startup and execution.
Core Concepts
Fibers
Lightweight concurrency (like Go routines). spawn { ... }.
Macros
Generate code at compile time (like Zig/Lisp).
Union Types
String | Int32. The compiler handles the branching.
Best Practices (2025)
Do:
- Use strict types in APIs: Help the compiler with
def foo(x : Int32). - Use
shards: Dependency manager. - Use
-Dpreview_mt: To test multithreading capabilities.
Don't:
- Don't use
eval: Crystal is compiled, there is no runtime eval.