try another way

package.json

@@ -19,7 +19,7 @@
     "build": "npm run compile && cp ./src/index-types.d.ts ./lib && gulp build && node ./rename-imports.mjs",
     "test:import": "npm run build  && node ./test/import-test.cjs && node ./test/import-test.mjs",
     "test": "npm run test:browser && npm run test:node",
-    "test:build": "PARCEL_WOKERS=0 parcel build ./test/unit-tests.html --dist-dir ./test-build --target none --public-url ./ --no-source-maps",
+    "test:build": "PARCEL_WORKER_BACKEND=process parcel build ./test/unit-tests.html --dist-dir ./test-build --target none --public-url ./ --no-source-maps",
     "test:browser": "npm run test:build && mocha-headless-chrome -f ./test-build/unit-tests.html -a disable-web-security -a no-sandbox -a disable-setuid-sandbox",
     "test:watch": "rm -rf ./.parcel-cache && PARCEL_WORKERS=0  parcel serve ./test/unit-tests.html ./test/manual-tests.html ./test/sandbox.html ./test/text-paths.html ./test/bunnies.html",
     "test:node": "ts-mocha -r ./test/node-global-setup.mjs -p ./test/tsconfig.json test/unit/**/*.ts --exit && npm run test:import",