diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c1b0ab3..4fe2125 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -18,7 +18,7 @@ jobs:
       - name: Use Node.js 12.11.0
         uses: actions/setup-node@v3
         with:
-          node-version: 12.11.0
+          node-version-file: '.nvmrc'
       - run: npm install
       - run: npm run lint
       - run: npm run build
diff --git a/.nvmrc b/.nvmrc
new file mode 100644
index 0000000..912dbfa
--- /dev/null
+++ b/.nvmrc
@@ -0,0 +1 @@
+19.5.0
diff --git a/src/calculate-contract-address.js b/src/calculate-contract-address.js
index c78ff3e..21d721c 100644
--- a/src/calculate-contract-address.js
+++ b/src/calculate-contract-address.js
@@ -8,7 +8,7 @@ import {
 } from './util';
 
 
-export default function calculateContractAddress(
+export function calculateContractAddress(
     creatorAddress,
     nonce
 ) {
diff --git a/src/create-identity.js b/src/create-identity.js
index d054b81..9dbe4b9 100644
--- a/src/create-identity.js
+++ b/src/create-identity.js
@@ -31,7 +31,7 @@ export function createPrivateKey(entropy) {
  * private-, public-Key and address
  * @param {Buffer?} entropy if provided, will use that as single random-source
  */
-export default function createIdentity(entropy) {
+export function createIdentity(entropy) {
     const privateKey = createPrivateKey(entropy);
     const wallet = new Wallet(privateKey);
     const identity = {
diff --git a/src/decrypt-with-private-key.js b/src/decrypt-with-private-key.js
index df92708..4baa7fc 100644
--- a/src/decrypt-with-private-key.js
+++ b/src/decrypt-with-private-key.js
@@ -8,7 +8,7 @@ import {
     removeLeading0x
 } from './util';
 
-export default function decryptWithPrivateKey(privateKey, encrypted) {
+export function decryptWithPrivateKey(privateKey, encrypted) {
 
     encrypted = parse(encrypted);
 
diff --git a/src/encrypt-with-public-key.js b/src/encrypt-with-public-key.js
index a34b10d..ac5613b 100644
--- a/src/encrypt-with-public-key.js
+++ b/src/encrypt-with-public-key.js
@@ -5,7 +5,7 @@ import {
     decompress
 } from './public-key';
 
-export default function encryptWithPublicKey(publicKey, message, opts) {
+export function encryptWithPublicKey(publicKey, message, opts) {
 
     // ensure its an uncompressed publicKey
     publicKey = decompress(publicKey);
diff --git a/src/index.js b/src/index.js
index 4a0da0f..ffd62c0 100644
--- a/src/index.js
+++ b/src/index.js
@@ -1,16 +1,16 @@
 
-import createIdentity from './create-identity';
+import { createIdentity } from './create-identity';
 import * as publicKey from './public-key';
-import decryptWithPrivateKey from './decrypt-with-private-key';
-import encryptWithPublicKey from './encrypt-with-public-key';
+import { decryptWithPrivateKey } from './decrypt-with-private-key';
+import { encryptWithPublicKey } from './encrypt-with-public-key';
 import * as cipher from './cipher';
-import publicKeyByPrivateKey from './public-key-by-private-key';
-import recover from './recover';
-import recoverPublicKey from './recover-public-key';
-import sign from './sign';
-import signTransaction from './sign-transaction';
-import txDataByCompiled from './tx-data-by-compiled';
-import calculateContractAddress from './calculate-contract-address';
+import { publicKeyByPrivateKey } from './public-key-by-private-key';
+import { recover } from './recover';
+import { recoverPublicKey } from './recover-public-key';
+import { sign } from './sign';
+import { signTransaction } from './sign-transaction';
+import { txDataByCompiled } from './tx-data-by-compiled';
+import { calculateContractAddress } from './calculate-contract-address';
 import * as hash from './hash';
 import * as hex from './hex';
 import * as vrs from './vrs';
diff --git a/src/public-key-by-private-key.js b/src/public-key-by-private-key.js
index e275e74..fc8c27f 100644
--- a/src/public-key-by-private-key.js
+++ b/src/public-key-by-private-key.js
@@ -12,7 +12,7 @@ import {
  * where 04 has stripped from left
  * @returns {string}
  */
-export default function publicKeyOfPrivateKey(privateKey) {
+export function publicKeyByPrivateKey(privateKey) {
     privateKey = addLeading0x(privateKey);
     const publicKeyBuffer = privateToPublic(toBuffer(privateKey));
     return publicKeyBuffer.toString('hex');
diff --git a/src/recover-public-key.js b/src/recover-public-key.js
index 63a58f8..ca8cbb8 100644
--- a/src/recover-public-key.js
+++ b/src/recover-public-key.js
@@ -14,7 +14,7 @@ import {
  * @param  {string} hash
  * @return {string} publicKey
  */
-export default function recoverPublicKey(signature, hash) {
+export function recoverPublicKey(signature, hash) {
     signature = removeLeading0x(signature);
 
     // split into v-value and sig
diff --git a/src/recover.js b/src/recover.js
index 26880d9..0f90d83 100644
--- a/src/recover.js
+++ b/src/recover.js
@@ -1,4 +1,4 @@
-import recoverPublicKey from './recover-public-key';
+import { recoverPublicKey } from './recover-public-key';
 import {
     toAddress as addressByPublicKey
 } from './public-key';
@@ -9,7 +9,7 @@ import {
  * @param  {string} hash
  * @return {string} address
  */
-export default function recover(sigString, hash) {
+export function recover(sigString, hash) {
     const pubkey = recoverPublicKey(sigString, hash);
     const address = addressByPublicKey(pubkey);
     return address;
diff --git a/src/sign-transaction.js b/src/sign-transaction.js
index f8b919b..380baa6 100644
--- a/src/sign-transaction.js
+++ b/src/sign-transaction.js
@@ -1,11 +1,11 @@
 
 import { Transaction } from '@ethereumjs/tx';
-import publicKeyByPrivateKey from './public-key-by-private-key';
+import { publicKeyByPrivateKey } from './public-key-by-private-key';
 import {
     toAddress as addressByPublicKey
 } from './public-key';
 
-export default function signTransaction(
+export function signTransaction(
     rawTx,
     privateKey,
     txOptions = {}
diff --git a/src/sign.js b/src/sign.js
index b2482e7..2c51e2c 100644
--- a/src/sign.js
+++ b/src/sign.js
@@ -13,7 +13,7 @@ import {
  * @param  {string} hash
  * @return {string} hexString
  */
-export default function sign(privateKey, hash) {
+export function sign(privateKey, hash) {
     hash = addLeading0x(hash);
     if (hash.length !== 66)
         throw new Error('EthCrypto.sign(): Can only sign hashes, given: ' + hash);
diff --git a/src/tx-data-by-compiled.js b/src/tx-data-by-compiled.js
index ac5d993..7da3634 100644
--- a/src/tx-data-by-compiled.js
+++ b/src/tx-data-by-compiled.js
@@ -1,6 +1,6 @@
 import { ContractFactory } from 'ethers';
 
-export default function txDataByCompiled(
+export function txDataByCompiled(
     abi,
     bytecode,
     args
diff --git a/test/unit.test.js b/test/unit.test.js
index 25a7d31..2293820 100644
--- a/test/unit.test.js
+++ b/test/unit.test.js
@@ -65,6 +65,7 @@ describe('unit.test.js', () => {
     describe('.publicKeyByPrivateKey()', () => {
         describe('positive', () => {
             it('should give the correct publicKey', () => {
+                console.dir(EthCrypto);
                 const publicKey = EthCrypto.publicKeyByPrivateKey(TEST_DATA.privateKey);
                 assert.equal(publicKey, TEST_DATA.publicKey);
             });