Scientist is a Ruby library developed by GitHub that enables safe, data-driven refactoring by running both the existing ("control") and new ("candidate") code paths in production, comparing their results and performance, while returning only the original output. It empowers developers to validate new implementations without affecting user-facing behavior.

Features

  • Wraps code blocks as use {} (control) and try {} (candidate) for experimentation
  • Randomizes execution order to avoid bias
  • Measures execution time for both control and candidate
  • Compares outputs and logs mismatches or exceptions
  • Allows configurable control over when candidate runs (e.g. percentage, ignore)
  • Hooks for custom result publishing (e.g. dashboards, alerts)

Project Samples

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License

MIT License

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Additional Project Details

Programming Language

Ruby

Related Categories

Ruby Frameworks

Registered

2025-07-31