diff --git a/packages/dnb-eufemia/jest.config.js b/packages/dnb-eufemia/jest.config.js
index d90de262ac4..fe51b1405e1 100644
--- a/packages/dnb-eufemia/jest.config.js
+++ b/packages/dnb-eufemia/jest.config.js
@@ -4,6 +4,7 @@ const config = {
   testRegex: '(/__tests__/\\.js|(\\.|/)(test|spec))\\.(js|jsx|ts)?$',
   modulePathIgnorePatterns: [
     'not_in_use',
+    '<rootDir>/scripts/release/__tests__/postbuild.test*',
     '<rootDir>/build/',
     '<rootDir>/assets/',
     '<rootDir>/stories/',
diff --git a/packages/dnb-eufemia/package.json b/packages/dnb-eufemia/package.json
index a0e7db53a82..dc2da36017f 100644
--- a/packages/dnb-eufemia/package.json
+++ b/packages/dnb-eufemia/package.json
@@ -21,7 +21,7 @@
     "audit:ci:yarn-outdated": "babel-node ./scripts/prepub/audit/toOpt && audit-ci --config ./audit-ci.json --package-manager=yarn --report-type full && babel-node ./scripts/prepub/audit/toDev",
     "build": "yarn build:prebuild && yarn build:esm && yarn build:copy",
     "prebuild:ci": "yarn build",
-    "postbuild:ci": "yarn build:types && yarn build:cjs && yarn build:es && yarn build:umd && yarn build:esm && yarn build:copy && yarn prettier:other && echo \"Can be enabled in future -> yarn build:resources\"",
+    "postbuild:ci": "./scripts/release/postbuild.sh",
     "build:cjs": "./scripts/release/babel-cjs.sh",
     "build:clean": "rm -rf build/**",
     "build:copy": "./scripts/release/copy-build-artifacts.sh",
@@ -63,6 +63,7 @@
     "skeleton:font": "nodemon --exec 'babel-node ./scripts/tools/createSkeletonFont.js'",
     "start": "yarn workspace dnb-eufemia-sandbox start",
     "test": "jest",
+    "test:build": "jest --ci --rootDir ./scripts/release",
     "test:ci": "jest --ci",
     "test:screenshots": "jest --config=./jest.config.screenshots.js --forceExit --detectOpenHandles",
     "test:screenshots:ci": "jest --config=./jest.config.screenshots.js --ci --forceExit --detectOpenHandles",
diff --git a/packages/dnb-eufemia/scripts/release/__tests__/postbuild.test.js b/packages/dnb-eufemia/scripts/release/__tests__/postbuild.test.js
new file mode 100644
index 00000000000..fd9f4e915b6
--- /dev/null
+++ b/packages/dnb-eufemia/scripts/release/__tests__/postbuild.test.js
@@ -0,0 +1,120 @@
+/**
+ * Test postbuild stage
+ * check if important files do exists
+ *
+ */
+
+import fs from 'fs-extra'
+import path from 'path'
+
+const buildStages = ['es', 'esm', 'cjs']
+
+describe('type definitions', () => {
+  it.each(buildStages)('has d.ts index file on stage %s', (stage) => {
+    const file = path.resolve(`./build/${stage}/index.d.ts`)
+    const exists = fs.existsSync(file)
+    expect(exists).toBe(true)
+  })
+
+  it.each(buildStages)(
+    'has correct Modal type definitions on stage %s',
+    (stage) => {
+      expect(
+        fs.existsSync(
+          path.resolve(`./build/${stage}/components/Modal.d.ts`)
+        )
+      ).toBe(true)
+
+      // To ensure babel did not compile the d.ts file
+      expect(
+        fs.readFileSync(
+          path.resolve(`./build/${stage}/components/modal/Modal.d.ts`),
+          'utf-8'
+        )
+      ).toMatch(/export interface/g)
+    }
+  )
+})
+
+describe('babel build', () => {
+  it.each(buildStages)('has correctly compiled on stage %s', (stage) => {
+    expect(
+      fs.existsSync(path.resolve(`./build/${stage}/components/Modal.js`))
+    ).toBe(true)
+
+    switch (stage) {
+      case 'cjs':
+        {
+          {
+            const content = fs.readFileSync(
+              path.resolve(`./build/${stage}/index.js`),
+              'utf-8'
+            )
+            expect(content).toContain(
+              'Object.defineProperty(exports, "__esModule", {'
+            )
+            expect(content).toContain(`var _default = {};`)
+
+            // Has extra cjs package
+            expect(
+              fs.existsSync(path.resolve(`./build/${stage}/package.json`))
+            ).toBe(true)
+          }
+
+          {
+            const content = fs.readFileSync(
+              path.resolve(`./build/${stage}/components/modal/Modal.js`),
+              'utf-8'
+            )
+            expect(content).toContain('var Modal = function')
+            expect(content).toMatch(/^"use strict";/g)
+          }
+        }
+        break
+
+      case 'esm':
+        {
+          {
+            const content = fs.readFileSync(
+              path.resolve(`./build/${stage}/index.js`),
+              'utf-8'
+            )
+            expect(content).toContain('export default {};')
+          }
+
+          const content = fs.readFileSync(
+            path.resolve(`./build/${stage}/components/modal/Modal.js`),
+            'utf-8'
+          )
+          expect(content).toContain('export { Modal as default };')
+          expect(content).toContain('core-js/modules/es')
+          expect(content).toContain(
+            'import _extends from "@babel/runtime/helpers/esm/extends";'
+          )
+        }
+        break
+
+      case 'es':
+        {
+          {
+            const content = fs.readFileSync(
+              path.resolve(`./build/${stage}/index.js`),
+              'utf-8'
+            )
+            expect(content).toContain('export default {};')
+          }
+
+          const content = fs.readFileSync(
+            path.resolve(`./build/${stage}/components/modal/Modal.js`),
+            'utf-8'
+          )
+          expect(content).toMatch(/export default class Modal extends/g)
+          expect(content).not.toContain('core-js/modules/es')
+          expect(content).toContain(
+            'import _extends from "@babel/runtime/helpers/esm/extends";'
+          )
+        }
+        break
+    }
+  })
+})
diff --git a/packages/dnb-eufemia/scripts/release/babel-cjs.sh b/packages/dnb-eufemia/scripts/release/babel-cjs.sh
index b3d2a7fd3c7..9a9d7d91447 100755
--- a/packages/dnb-eufemia/scripts/release/babel-cjs.sh
+++ b/packages/dnb-eufemia/scripts/release/babel-cjs.sh
@@ -16,6 +16,10 @@ babel ./src \
 
 echo 'Building cjs done!'
 
-echo 'Copy .d.ts files ...'
+echo 'Copy .d.ts files to cjs ...'
 
 OUT_DIR=./build/cjs babel-node ./scripts/release/copyTypeScriptDefinitionFiles.js
+
+echo 'Copy extra cjs package.json ...'
+
+cp ./src/cjs/package.json ./build/cjs/package.json
diff --git a/packages/dnb-eufemia/scripts/release/babel-es.sh b/packages/dnb-eufemia/scripts/release/babel-es.sh
index 018d1643579..49eb3ed5f49 100755
--- a/packages/dnb-eufemia/scripts/release/babel-es.sh
+++ b/packages/dnb-eufemia/scripts/release/babel-es.sh
@@ -16,6 +16,6 @@ babel ./src \
 
 echo 'Building es done!'
 
-echo 'Copy .d.ts files ...'
+echo 'Copy .d.ts files to es ...'
 
 OUT_DIR=./build/es babel-node ./scripts/release/copyTypeScriptDefinitionFiles.js
diff --git a/packages/dnb-eufemia/scripts/release/babel-esm.sh b/packages/dnb-eufemia/scripts/release/babel-esm.sh
index 6125261110b..46557834922 100755
--- a/packages/dnb-eufemia/scripts/release/babel-esm.sh
+++ b/packages/dnb-eufemia/scripts/release/babel-esm.sh
@@ -16,6 +16,6 @@ babel ./src \
 
 echo 'Building esm done!'
 
-echo 'Copy .d.ts files ...'
+echo 'Copy .d.ts files to esm ...'
 
 OUT_DIR=./build/esm babel-node ./scripts/release/copyTypeScriptDefinitionFiles.js
diff --git a/packages/dnb-eufemia/scripts/release/postbuild.sh b/packages/dnb-eufemia/scripts/release/postbuild.sh
new file mode 100755
index 00000000000..e4134fb1e49
--- /dev/null
+++ b/packages/dnb-eufemia/scripts/release/postbuild.sh
@@ -0,0 +1,15 @@
+#!/bin/bash
+
+echo 'Postbuild started ...'
+
+yarn build:types
+yarn build:cjs
+yarn build:es
+yarn build:esm
+yarn build:umd
+echo 'Can be enabled in future if needed -> yarn build:resources'
+yarn build:copy
+yarn prettier:other
+yarn test:build
+
+echo 'Postbuild done!'