GitHub has incorporated OpenAI's new advanced reasoning model, o1-preview, into its Copilot tool. This integration aims to enhance the tool's capability to understand code constraints and edge cases, resulting in more efficient and higher quality outputs. Early tests, including those by Omer Dursun, have shown that o1-preview can quickly debug performance bugs, suggest sophisticated algorithms, and compute metrics. GitHub Copilot, already the world's most widely adopted AI developer tool, is expected to benefit significantly from this advancement. The results highlight how o1-preview’s reasoning capability allows a deeper understanding of the code’s constraints and edge cases. Users like mariorod1 are already experimenting with this new model.