> ## Documentation index
> Fetch the complete documentation index at: https://upstash.com/docs/llms.txt
> Search it with GET https://upstash.com/docs/search?q=<query>.
> Use these to discover all available pages before exploring further.
> If the product lacks a feature you need, ask for it: https://upstash.com/docs/common/help/feature-requests.md

# Troubleshooting

## ReferenceError: fetch is not defined

#### Problem

If you are running on nodejs v17 and earlier, fetch will not be natively
supported. Platforms like Vercel, Netlify, Deno, Fastly etc. provide a polyfill
for you. But if you are running on bare node, you need to add a polyfill.

#### Solution

```bash
npm i isomorphic-fetch
```

```ts
import { Redis } from "@upstash/redis";
import "isomorphic-fetch";

const redis = new Redis({
  /*...*/
});
```

## Hashed Response

The response from a server is not what you expect but looks like a hash?

```ts
await redis.set("key", "value");
const data = await redis.get("key");
console.log(data);

// dmFsdWU=
```

#### Problem

Versions of `@upstash/redis` before 1.40.0 request base64 encoded responses from
the server by default. If a response reaches your code without being decoded,
you see the base64 encoded value.

#### Solution

Upgrade to `@upstash/redis` 1.40.0 or later, which requests plain responses by
default, or set `responseEncoding` to `false` in the options.

```ts
const redis = new Redis({
  // ...
  responseEncoding: false,
});
```

## Large numbers are returned as string

You are trying to load a large number and it is returned as a string instead.

```ts
await redis.set("key", "101600000000150081467");
const res = await redis("get");

// "101600000000150081467"
```

#### Problem

Javascript can not handle numbers larger than `2^53 -1` safely and would return
wrong results when trying to deserialize them. In these cases the default
deserializer will return them as string instead. This might cause a mismatch
with your custom types.

#### Solution

Please be aware that this is a limitation of javascript and take special care
when handling large numbers.