diff --git a/why_not_llms.md b/why_not_llms.md
index 3f317c6..d83d5c1 100644
--- a/why_not_llms.md
+++ b/why_not_llms.md
@@ -94,6 +94,7 @@ There is increasing evidence to show that LLMs negatively impact developers' cod
 * In an [Anthropic study](https://www.anthropic.com/research/AI-assistance-coding-skills), learners using LLMs demonstrated lower learning rates on average compared to learners not using LLMs.
 * [A recent study uses the term "cognitive surrender"](https://papers.ssrn.com/sol3/papers.cfm?abstract_id=6097646) to describe the way humans tend to offload key critical thinking skills onto LLMs, even when the output is wrong.
 * A paper entitled ["AI Assistance Reduces Persistence and Hurts Independent Performance"](https://arxiv.org/abs/2604.04721) from April 2026 by academics from MIT, Oxford, UCLA, and Carnegie Mellon showed alarming evidence that performing a variety of tasks with the help of AI for only 10 minutes causes "inpaired unassisted performance and reduced persistence". The researchers noted that "although AI assistance improves performance in the short-term, people perform significantly worse without AI and are more likely to give up"; they also pointed out that "these findings are particularly concerning because persistence is foundational to skill acquisition and is one of the strongest predictors of long-term learning".
+* [Arstechnica: Study finds AI tools made open source software developers 19 percent slower](https://arstechnica.com/ai/2025/07/study-finds-ai-tools-made-open-source-software-developers-19-percent-slower/)
 
 ### Infosec risks