Lindsey Simon, VP of Engineering at Vercel, discusses the evolving role of AI in engineering, emphasizing the shift towards "vibe-codeable" systems where ideas drive the coding process, rather than simply accelerating code generation. He highlights that AI's impact on engineering velocity depends on the flexibility of existing systems, suggesting that modernizing codebases will unlock greater efficiency. As AI enhances code generation, the focus shifts to design clarity and articulating quality prompts, marking a shift from execution to ideation as the bottleneck. AI-driven test loops are transforming test-driven development into a powerful feedback mechanism, making it crucial for engineers to pass tests rather than obsess over implementation details. Vercel's hiring criteria remain unchanged, but candidates' ability to use AI for creative problem-solving and optimization is now a priority, signaling a move towards personal software where engineers build tools tailored to their individual needs.