CR
Crystal Performance
Performance optimization for Crystal using fibers, channels, compile flags, and allocation-aware patterns
Details
Language / Topic
CrystalCategory
Performance
Rules
balanced
- Build release binaries with `crystal build --release` to enable LLVM optimizations — never benchmark debug builds.
- Use `struct` instead of `class` for frequently allocated small objects — structs are stack-allocated and avoid GC heap pressure entirely.
- Use `IO::Memory` for in-memory string building instead of string concatenation — `String.build { |io| io << a << b }` avoids intermediate string allocations.
- Use `Channel(T)` and `Fiber.yield` for cooperative concurrency — Crystal's scheduler multiplexes fibers over OS threads using non-blocking I/O.