ADR-004: @heygen/streaming-avatar Must Be Inlined in vitest

Decision

vitest.config.ts includes server: { deps: { inline: ['@heygen/streaming-avatar'] } }.

Context

@heygen/streaming-avatar declares "type": "module" (ESM package) but its "main" field points to a CJS file. When vitest's Node runner loads it, it hits the CJS file in an ESM context and throws:

ReferenceError: exports is not defined in ES module scope

Fix

server.deps.inline forces Vite to process the package through its bundler pipeline, which uses the "module" field (the actual ESM build) instead of "main". This resolves the CJS/ESM conflict.

Consequence

The SDK is bundled into the test output rather than loaded from node_modules at runtime. No functional impact on test correctness. Tests run normally.