Part 1 of a series. The build follows in subsequent posts. Three frontend frameworks in the same business domain is the rule, not the exception. One team adopted Angular years ago. Another fell in love with React. The M&A team brought a Vue app along. The standard answer is Rewrite — years, millions, often failing. There is another answer: let them live together. This post walks through the architectural spec for a small but real demo that does exactly that — Angular, React, and Svelte inside a single workspace, sharing one business context. Call it Frankenstein-Driven Architecture. The Frankenstein Reality Heterogeneity in enterprise frontends isn't a temporary mess to be cleaned up. It's a permanent condition. Acquisitions bring new stacks. Teams pick what they know. Industry tides shift; once-favored frameworks fall out of fashion long before the apps written in them stop earning money. The rewrite-first culture treats this as a problem to be eliminated.…