React Native
25:04
9/3/2025

Ottrelite: Tracing Framework for React Native

Presented
React Universe Conf
Speakers
Artur Morys-Magiera
Software Engineer
@
Callstack
Dominik Dolny
Software Engineer
@
Callstack

Tracing React Native internals has always been possible, but never this flexible.At React Universe Conf 2025, Artur Morys-Magiera and Dominik Dolny (Senior Engineers at Callstack) introduce Ottrelite, a unified and extensible tracing framework for React Native. Ottrelite re-enables the existing Systrace JS API through Nitro Modules and provides a plugin system for plugging in any native tracing backend.

  • Why tracing React Native internals has been difficult with prebuilt artifacts and missing plugin support
  • How Ottrelite avoids building React Native from source while still enabling deep instrumentation
  • Support for multiple languages: JavaScript, Kotlin/Java, Swift/Objective-C, and C++
  • Built-in backends: Tracy, Android ATrace, and iOS os_signpost, plus the ability to bring your own
  • Development vs. production workflows: profiling with Tracy, telemetry with OpenTelemetry and tools like Grafana, Jaeger, or Prometheus
  • Automatic component instrumentation with a Babel plugin, plus hooks for custom tracing and metadata

Ottrelite bridges the gap between React Native DevTools and modern observability needs, making it easier than ever to trace, profile, and monitor apps across platforms.

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