at the end of the day, it was inevitable

frontend/app/common/constants.js

@@ -0,0 +1,20 @@
+import appConfig from '../appConfig.js';
+
+const { appEnv, hubSpotportalID } = appConfig;
+
+// when `npm start` server in local
+export const isDevelopment = process.env.NODE_ENV === 'development';
+
+// when `npm run build`
+export const isProduction = process.env.NODE_ENV === 'production';
+
+// when run locally or build is generated for corresponding sites
+export const isLive = appEnv === 'live';
+export const isStaging = appEnv === 'staging';
+export const isLocal = appEnv === 'local';
+
+export const errorConstants = {
+  'Bad credentials.': 'badCredentials'
+};
+
+export const hubspotBaseURL = `https://api.hsforms.com/submissions/v3/integration/submit/${hubSpotportalID}`;