<p>This <a href="https://simonwillison.net/2026/May/14/mitchell-hashimoto/">Mitchell Hashimoto quote</a> about Bun migrating from Zig to Rust reminded me of a similar conversation I had at a conference last week.</p> <p>I was talking to someone who worked for a medium sized technology company with a pair of legacy/<a href="https://simonwillison.net/2018/Jul/17/mark-norman-francis/">legendary</a> iPhone and Android apps.</p> <p>They told me they had just completed a coding-agent driven rewrite of
The content identifies a paradigm shift in software engineering: AI reduces the 'switching cost' of tech stacks, making architectural decisions less permanent and challenging the traditional wisdom that rewrites are prohibitively expensive.