PicoRuby Development Constraints

Memory constraints and stdlib limitations for ESP32 PicoRuby development.

Memory & Runtime Limits

• Total heap: 520KB (strict limit)
• Nesting depth: Avoid deep recursion; prefer iterative solutions
• String handling: Pre-allocate when possible; avoid repeated concatenation
• Arrays: Use fixed-size when known; minimize dynamic growth during tight loops

PicoRuby vs CRuby

| Feature | PicoRuby | CRuby | |---------|----------|-------| | Gems | ❌ No bundler/gems | ✅ Full ecosystem | | stdlib | Minimal (R2P2-ESP32 only) | Complete stdlib | | Memory | ~520KB heap | GB+ available | | GC | Simple mark-sweep | Complex generational | | Float math | ⚠️ Limited precision | Full IEEE 754 |

PicoRuby-safe stdlib

Available:

• Array#each, #map, #select (avoid #each_with_index in tight loops)
• Hash (simple key-value)
• String (basic methods, avoid regex for embedded)
• Time (limited; ESP32 time depends on system clock)
• File (via R2P2-ESP32 abstraction)

Unavailable:

• Regex (use string matching instead)
• Threads (single-threaded runtime)
• Fiber/Enumerator (complex control flow not needed)