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Ethern Myth
Ethern Myth

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Node.Js Express Typescript Deployment on Vercel

Just came across the web and tried to find good documentation on deploying Node.js Express Typescript to Vercel. It was not clear at all with my findings. Important instructions were missing, but I have customized some changes and got it to work in few minutes.

Create a vercel.json in the project root of your project if not existing already.

Add this code and change the src path according to your project setup.

"version": 2,
"builds": [
"src": "src/api/index.ts",
"use": "@vercel/node"
"routes": [
"src": "/(.*)",
"dest": "src/api/index.ts"

I had my project setup with src folder and added the api folder to the src folder.

Inside the api folder, I create an index.ts file.

The index.ts file has this code:

import cors from "cors";
import dotenv from "dotenv";
import bodyParser from "body-parser";
import compression from "compression";
import helmet from "helmet";
import express from "express";
import router from "../routes/prisma";


const app = express();
origin: "
app.use(bodyParser.urlencoded({ extended: true }));
app.use(helmet.crossOriginResourcePolicy({ policy: "cross-origin" }));
app.use("/api", router);
", (req, res) => {
res.status(400).json({ error: Route ${req.originalUrl} not found });

export default app;

The most import code here is to

export default app;

That way this becomes serverless just like Vercel Serverless functions.

The router defines the all routes for the api itself.

Since I am using Prisma and with addition of mongo backup, I structured the folders for every ORM the project support.

Last thing was to add this precious line to the package.json:

"vercel-build": "yarn generate",

This line, gets prisma to initialize the client and be of use to the whole project.

The "vercel-build" works for any build you wish to have when using node.

I hope this was clear in a way to help with deploying node express to Vercel as serverless.

Leave a comment for any information you need from this.


Top comments (3)

ethernmyth profile image
Ethern Myth • Edited

First check if typeorm does not need to initialise it's client. I haven't used typeorm to ensure this yet or deployed with typeorm.

For vercel-build: yarn generate

"This line, gets prisma to initialize the client and be of use to the whole project."

Vercel-build will be necessary if any scripts need to be done during the deployment like migrations. You can use your npm to run the scripts.

If you want the full answer. I can try to quickly test it out and re-comment on this.

ethernmyth profile image
Ethern Myth

I tested the typeorm deployment and I found a good issue why?

List of currently supported and I think why it worked well with Prisma.

Seem likes Vercel does not support the ORM and found this docs Using an ORM to access your database...

But that did not stop only there.

I rewrote the API for testing and still got 500: Internal Server when hitting an endpoint with AppDataSource configured, which is from typeorm. I tried this and registered, but still did not work.

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Had to also change this imports from this to the next image:

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To this, to get the testing endpoints:
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If your project depends on typeorm, please try to find alternative deployments environment like, or migrate to the supported ORM for Vercel. Or finally, try to write a custom bridge pattern to merge the both, which is just an idea. 😁

All the best.

lakshmie2207 profile image
Lakshmi • Edited

I am using typeorm instead of prisma and using npm instead of yarn. So what will be the changes in the code ?