--- title: "muttest 0.2.0: More Mutators, Better Reporting, and Parallel Execution" url: https://daily.dev/posts/muttest-0-2-0-more-mutators-better-reporting-and-parallel-execution-ejfmdpscv source_url: https://www.r-bloggers.com/2026/05/muttest-0-2-0-more-mutators-better-reporting-and-parallel-execution type: article source: "R-bloggers" published: 2026-05-15T15:42:59.751Z updated: 2026-05-15T15:43:24.019Z tags: ["testing", "r", "mutation-testing"] reading_time: 9 upvotes: 0 comments: 0 language: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # muttest 0.2.0: More Mutators, Better Reporting, and Parallel Execution **[R-bloggers](https://daily.dev/sources/rbloggers)** · 9 min read · 0 upvotes · 0 comments ## Summary muttest 0.2.0 is a new release of the R mutation testing package that significantly expands its capabilities. Key additions include a larger mutator library with 12+ new individual mutators (boolean_literal, negate_condition, numeric_increment, delete_statement, etc.) and preset collections for common patterns. The reporter now surfaces survived mutants directly in output, making it easier to identify test gaps. Parallel execution via {mirai} reduces run time on larger codebases, and per-mutant timeouts prevent infinite loops from stalling runs. The release also explains why mutation testing catches bugs that 100% code coverage misses, and notes its value for validating LLM-generated tests. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [What is mutation testing?](https://daily.dev/posts/what-is-mutation-testing--kyhatcxk1) · CircleCI · 1 upvotes · 1 comments - [Mutation testing comes to DAML](https://daily.dev/posts/mutation-testing-comes-to-daml-fofawezvf) · Trail of Bits Blog · 0 upvotes · 0 comments --- Tags: [#testing](https://daily.dev/tags/testing), [#r](https://daily.dev/tags/r), [#mutation-testing](https://daily.dev/tags/mutation-testing) [View this post on daily.dev](https://daily.dev/posts/muttest-0-2-0-more-mutators-better-reporting-and-parallel-execution-ejfmdpscv)