diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index 01b1948..c7dcbfc 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -32,13 +32,16 @@ jobs:
             echo "::set-output name=version_changed::false";
           fi
       - name: Use Node.js ${{ matrix.node-version }}
-        if: steps.check_version.outputs.version_changed == 'true'
         uses: actions/setup-node@v4
         with:
           node-version: ${{ matrix.node-version }}
           registry-url: "https://registry.npmjs.org"
-      - run: npm install
-      - run: npm run build
-      - run: npm publish --provenance --access public
+
+      - name: Publish to npm
+        if: steps.check_version.outputs.version_changed == 'true'
+        run: |
+          npm ci
+          npm run build
+          npm publish --provenance --access public
         env:
           NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
diff --git a/package-lock.json b/package-lock.json
index ee04496..8a25670 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -971,6 +971,12 @@
       "resolved": "src/eip4337",
       "link": true
     },
+    "node_modules/@qng/meerchange-contracts": {
+      "version": "0.0.1",
+      "resolved": "https://registry.npmjs.org/@qng/meerchange-contracts/-/meerchange-contracts-0.0.1.tgz",
+      "integrity": "sha512-yZS9HDCErQyqcFO1i/2vQ37mIwF/xI4W9MPTbJ1RNFITpIsfrcIfAwv+5zgUx7FjfRk4gJ4yp9b/2JGrMyBAOQ==",
+      "dev": true
+    },
     "node_modules/@tsconfig/node10": {
       "version": "1.0.11",
       "resolved": "https://registry.npmjs.org/@tsconfig/node10/-/node10-1.0.11.tgz",
@@ -3066,11 +3072,13 @@
       }
     },
     "src/eip4337": {
+      "name": "@qng/eip4337-sdk",
       "version": "0.6.0",
       "license": "MIT",
       "devDependencies": {
         "@account-abstraction/sdk": "^0.6.0",
-        "@qng/eip4337-contracts": "^0.6.0"
+        "@qng/eip4337-contracts": "^0.6.0",
+        "@qng/meerchange-contracts": "^0.0.1"
       }
     }
   }
diff --git a/src/eip4337/index.ts b/src/eip4337/index.ts
index da79255..2edfef5 100644
--- a/src/eip4337/index.ts
+++ b/src/eip4337/index.ts
@@ -8,4 +8,11 @@ import {
   HttpRpcClient,
   BaseAccountAPI,
 } from "./qngAccountAPI";
-export { QngAccountAPI, PaymasterAPI, HttpRpcClient, BaseAccountAPI };
+import { MeerChangeAPI } from "./meerchange";
+export {
+  QngAccountAPI,
+  PaymasterAPI,
+  HttpRpcClient,
+  BaseAccountAPI,
+  MeerChangeAPI,
+};
diff --git a/src/eip4337/meerchange.ts b/src/eip4337/meerchange.ts
new file mode 100644
index 0000000..00840bc
--- /dev/null
+++ b/src/eip4337/meerchange.ts
@@ -0,0 +1,47 @@
+import * as contracts from "@qng/meerchange-contracts";
+
+import { Provider } from "@ethersproject/providers";
+import { ethers } from "ethers";
+export class MeerChangeAPI {
+  meerchangeContract: any;
+  meerchangeAddr: string;
+  provider: Provider;
+  constructor(params: any) {
+    this.provider = params.provider;
+    this.meerchangeAddr = params.meerchangeAddr;
+  }
+  async _getMeerChangeContract() {
+    if (this.meerchangeContract == null) {
+      this.meerchangeContract = await contracts.MeerChange__factory.connect(
+        await this.getMeerChangeAddress(),
+        this.provider
+      );
+    }
+    return this.meerchangeContract;
+  }
+  async encodeExport4337(
+    txid: string,
+    idx: number,
+    fee: number,
+    signature: string
+  ) {
+    if (!txid.startsWith("0x")) {
+      txid = `0x${txid}`;
+    }
+    const meerchangeContract = await this._getMeerChangeContract();
+    return meerchangeContract.interface.encodeFunctionData("export4337", [
+      ethers.utils.hexZeroPad(txid, 32),
+      idx,
+      fee,
+      signature,
+    ]);
+  }
+
+  async getMeerChangeAddress() {
+    // TODO
+    // {
+    //  "id":1,"jsonrpc":"2.0","method":"qng_getMeerChangeAddress","params":[]
+    //}
+    return this.meerchangeAddr;
+  }
+}
diff --git a/src/eip4337/package.json b/src/eip4337/package.json
index d4732ff..a8a8268 100644
--- a/src/eip4337/package.json
+++ b/src/eip4337/package.json
@@ -14,6 +14,7 @@
   },
   "keywords": [
     "sdk",
+    "qitmeer",
     "qng",
     "smart",
     "contracts",
@@ -26,6 +27,7 @@
   },
   "devDependencies": {
     "@qng/eip4337-contracts": "^0.6.0",
+    "@qng/meerchange-contracts": "^0.0.1",
     "@account-abstraction/sdk": "^0.6.0"
   }
 }