diff --git a/packages/core/npm/esm/dev.js b/packages/core/npm/esm/dev.js
new file mode 100644
index 000000000..988a5a2f4
--- /dev/null
+++ b/packages/core/npm/esm/dev.js
@@ -0,0 +1,18 @@
+import {
+  i18n as i18nProd,
+  setupI18n as setupI18nProd,
+  formats as formatsProd,
+  I18n as I18nProd
+} from './dev.production.min';
+
+import {
+  i18n as i18nDev,
+  setupI18n as setupI18nDev,
+  formats as formatsDev,
+  I18n as I18nDev
+} from './dev.development';
+
+export const i18n = process.env.NODE_ENV === 'production' ? i18nProd : i18nDev;
+export const setupI18n = process.env.NODE_ENV === 'production' ? setupI18nProd : setupI18nDev;
+export const formats = process.env.NODE_ENV === 'production' ? formatsProd : formatsDev;
+export const I18n = process.env.NODE_ENV === 'production' ? I18nProd : I18nDev;
\ No newline at end of file
diff --git a/packages/core/npm/esm/index.js b/packages/core/npm/esm/index.js
index 3b2800036..01cf71e7b 100644
--- a/packages/core/npm/esm/index.js
+++ b/packages/core/npm/esm/index.js
@@ -3,14 +3,14 @@ import {
     setupI18n as setupI18nProd,
     formats as formatsProd,
     I18n as I18nProd
-} from './core.esm';
+} from './core.production.min';
 
 import {
     i18n as i18nDev,
     setupI18n as setupI18nDev,
     formats as formatsDev,
     I18n as I18nDev
-} from './dev.esm';
+} from './core.development';
 
 export const i18n = process.env.NODE_ENV === 'production' ? i18nProd : i18nDev;
 export const setupI18n = process.env.NODE_ENV === 'production' ? setupI18nProd : setupI18nDev;
diff --git a/scripts/build/rollup.js b/scripts/build/rollup.js
index 71944eb0e..c804bf1ea 100644
--- a/scripts/build/rollup.js
+++ b/scripts/build/rollup.js
@@ -19,7 +19,6 @@ const codeFrame = require("babel-code-frame")
 const babelConfig = require("./babel.config")
 
 const Modules = require("./modules")
-const Bundles = require("./bundles")
 const Packaging = require("./packaging")
 
 const UMD_DEV = "UMD_DEV"
@@ -27,6 +26,7 @@ const UMD_PROD = "UMD_PROD"
 const NODE_DEV = "NODE_DEV"
 const NODE_PROD = "NODE_PROD"
 const ESM_PROD = "ESM_PROD"
+const ESM_DEV = "ESM_DEV"
 
 const extensions = [".js", ".ts", ".tsx"]
 
@@ -71,6 +71,7 @@ function getFormat(bundleType) {
     case NODE_PROD:
       return 'cjs'
     case ESM_PROD:
+    case ESM_DEV:
       return 'es'
   }
 }
@@ -79,13 +80,13 @@ function getFilename(bundle, bundleType) {
   const filename = bundle.label || bundle.entry
   switch (bundleType) {
     case NODE_DEV:
+    case ESM_DEV:
     case UMD_DEV:
       return `${filename}.development.js`
     case UMD_PROD:
     case NODE_PROD:
-      return `${filename}.production.min.js`
     case ESM_PROD:
-      return `${filename}.esm.js`
+      return `${filename}.production.min.js`
   }
 }
 
@@ -93,6 +94,7 @@ function isProductionBundleType(bundleType) {
   switch (bundleType) {
     case UMD_DEV:
     case NODE_DEV:
+    case ESM_DEV:
       return false
     case UMD_PROD:
     case NODE_PROD:
@@ -291,7 +293,7 @@ async function build(bundle, bundleType) {
     ),
   }
   const [mainOutputPath, ...otherOutputPaths] = Packaging.getBundleOutputPaths(
-    bundleType === ESM_PROD ? "ESM" : "UNIVERSAL",
+    bundleType === ESM_PROD || bundleType === ESM_DEV ? "ESM" : "UNIVERSAL",
     filename,
     packageName
   )
@@ -320,6 +322,7 @@ async function build(bundle, bundleType) {
 module.exports = async function (bundle) {
   await build(bundle, NODE_DEV)
   await build(bundle, NODE_PROD)
+  await build(bundle, ESM_DEV)
   await build(bundle, ESM_PROD)
   // await build(bundle, UMD_DEV)
   // await build(bundle, UMD_PROD)