This repo demonstrates an issue with reproducible builds in vue-cli. To reproduce, run:

npm i
sudo rm -r node_modules/.cache/; npx vue-cli-service build; git status

About half the time, this will show changes in dist/, even though no files have changed in src.

The changes look like the adding or removing of three lines of whitespace, and the adding or removing of these lines:

/* harmony import */ var core_js_modules_es6_array_iterator__WEBPACK_IMPORTED_MODULE_0__ = __webpack_require__("cadf");
/* harmony import */ var core_js_modules_es6_array_iterator__WEBPACK_IMPORTED_MODULE_0___default = /*#__PURE__*/__webpack_require__.n(core_js_modules_es6_array_iterator__WEBPACK_IMPORTED_MODULE_0__);
/* harmony import */ var core_js_modules_es6_promise__WEBPACK_IMPORTED_MODULE_1__ = __webpack_require__("551c");
/* harmony import */ var core_js_modules_es6_promise__WEBPACK_IMPORTED_MODULE_1___default = /*#__PURE__*/__webpack_require__.n(core_js_modules_es6_promise__WEBPACK_IMPORTED_MODULE_1__);
/* harmony import */ var core_js_modules_es7_promise_finally__WEBPACK_IMPORTED_MODULE_2__ = __webpack_require__("097d");
/* harmony import */ var core_js_modules_es7_promise_finally__WEBPACK_IMPORTED_MODULE_2___default = /*#__PURE__*/__webpack_require__.n(core_js_modules_es7_promise_finally__WEBPACK_IMPORTED_MODULE_2__);

The changes (including whitespace changes) can be avoided by disabling vue's default polyfills in babel.config.js.