Repeated vinext builds currently leave stale hashed server chunks in dist/server. Workers deployments with no_bundle upload every matched JS module, so stale chunks count against Worker size limits.
The CLI assumed Vite's per-environment emptyOutDir would remove old output, but the multi-environment build and hybrid Pages Router pass preserve dist/server artifacts.
Clean the vinext dist output once immediately before the Vite build starts, while preserving build.emptyOutDir: false as the escape hatch. Add focused tests for default cleaning, explicit preservation, and outside-root safety.
Nathan Nguyen