# Harness for mutation testing
**URL:** https://racket.discourse.group/t/harness-for-mutation-testing/3206
**Category:** Questions & Answers
**Tags:** question
**Created:** [October 7, 2024, 10:38pm UTC](https://racket.discourse.group/t/harness-for-mutation-testing/3206 "2024-10-07T22:38:52Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@SamPhillips](https://racket.discourse.group/u/SamPhillips)
#### Post date: [October 7, 2024, 10:38pm UTC](https://racket.discourse.group/t/harness-for-mutation-testing/3206/1 "2024-10-07T22:38:52Z")
Is there are harness to streamline some of the setup of mutation testing (using [mutate](https://pkgs.racket-lang.org/package/mutate)) for a package? This seems like it could be a neat `raco` command...
Tagging: @CharlieRay668 @jbclements @llazarek
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### Author:  [@jbclements](https://racket.discourse.group/u/jbclements)
#### Post date: [October 9, 2024, 2:59am UTC](https://racket.discourse.group/t/harness-for-mutation-testing/3206/2 "2024-10-09T02:59:23Z")
Yes, possibly. I think the hardest part of this would likely be choosing _which_ mutations to apply; my understanding is that this is currently one of those mostly-guesswork practices.
As a start, I can certainly (check with Charlie and then probably) open-source the code that he wrote, which drives lukas lazarek's mutate library.
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### Author:  [@SamPhillips](https://racket.discourse.group/u/SamPhillips)
#### Post date: [October 9, 2024, 3:04am UTC](https://racket.discourse.group/t/harness-for-mutation-testing/3206/3 "2024-10-09T03:04:03Z")
> [@jbclements](#):
>
> Yes, possibly. I think the hardest part of this would likely be choosing _which_ mutations to apply; my understanding is that this is currently one of those mostly-guesswork practices.
Yeah I figured the harness that Charlie used was using hardwired mutations, but it could be a good starting point. If a `raco` tool was made choosing mutations from command line (or some other input) would probably be needed.
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### Author:  [@EmEf](https://racket.discourse.group/u/EmEf)
#### Post date: [October 9, 2024, 10:55am UTC](https://racket.discourse.group/t/harness-for-mutation-testing/3206/4 "2024-10-09T10:55:02Z")
Lukas’s framework enables people to write their own mutators; Charlie did add some new ones.