The post proposes building extensible web software by letting users safely run LLM-generated code snippets as custom extensions, rather than developers bloating products with every feature request. Morrell argues that users have long-tail needs the static app can't serve, and LLMs dramatically lower the authoring cost—but the hard part is the sandbox: you need cheap execution, fast cold starts, strict resource limits, strong isolation, and a capability-based permissions model so user code only accesses what you explicitly grant it (not raw API keys). He walks through isolation technologies (V8 isolates, WASM, MicroVMs) and uses Salesforce's Apex platform (since 2007) as proof this scales, then advocates Cloudflare Workers' Dynamic Workers as the production-ready option today. The post includes live runnable demos: a scraper harness where you paste a URL and custom JS transforms the output (PDF-to-markdown, feed digests, etc.). The core insight is sound—capability-based access beats ambient authority—but the source doesn't detail deployment friction, how to surface capabilities to LLMs efficiently at scale, or evidence that users actually share extensions they write, which would matter for the "platform" framing to stick.