PBT – A property-based testing library for Ruby
Hello HN, I introduce a property-based testing tool for Ruby. Ruby's ease of test-writing and rich ecosystem are widely acclaimed. However, property-based testing is not as widely used as in other languages such as Haskell or Elixir, and I think this is because there is no de facto testing tool. This gem currently not only has the basic functionality of stateless property-based testing but also has the following features: - Support verbose mode that allows you to see its shrinking procedure and algorithms. - Support several concurrency/parallel executions of each test. As of now,…
PBT – A property-based testing library for Ruby launched on May 22, 2024 with 196 votes, #264 of 4,539 launches that month and more than 95% of that year's launches. The site was still online in September 2026, 2 years on.
In plain words
PBT is a property-based testing library for Ruby that generates test cases automatically to find edge cases and failures. It includes stateless property testing with a verbose mode to observe shrinking procedures and supports concurrent or parallel test execution via Ractor, Thread, or Process. Designed for Ruby developers seeking property-based testing tools comparable to those available in languages like Haskell and Elixir.
written from the facts on this page · September 2026
From the sources
Property-Based Testing tool for Ruby that supports concurrency with Ractor. - ohbarye/pbt
In the maker’s words, at launch
Hello HN, I introduce a property-based testing tool for Ruby. Ruby's ease of test-writing and rich ecosystem are widely acclaimed. However, property-based testing is not as widely used as in other languages such as Haskell or Elixir, and I think this is because there is no de facto testing tool. This gem currently…
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Source: Show HN post ↗ · launch text quoted in part