Problem

The first failure showed up in slate-hyperscript, but the underlying issue was broader: workspace package-name imports were leaning on built dist/ entries.

That works until it doesn't.

Under Yarn PnP, once a package root resolves through dead or stale dist/ output, tests and source-time tooling can fail for reasons that have nothing to do with the actual source package.

Root Cause

Most workspace packages had src/index.ts, but no root index.ts.

That left package-name imports overly dependent on published-entry metadata and prebuilt output even inside the workspace itself.

Solution

Use both:

1. a tiny live root source entry in each workspace package:

export * from './src'

for:

• slate
• slate-history
• slate-react
• slate-dom
• slate-browser
• slate-hyperscript

2. a test-time module alias layer for Babel/Mocha lanes so package-name imports resolve to live source instead of stale dist/ when dist/ happens to exist

Why This Works

The root entry gives the workspace a source-resolvable package fallback without changing the real authored module surface.

The Babel alias closes the other half of the trap: if dist/ exists, Node/PnP can still prefer it. For source-time proof lanes, the alias forces live source.

Prevention

• If a workspace package is meant to be imported by package name during local proof or test work, give it a live root source entry.
• If source-time test lanes use Babel/Mocha, alias package names to source so stale dist/ cannot silently win.
• Do not let workspace reliability depend on dist/ luck.
• Tiny package-root files beat mysterious resolution failures every time.