# Problems running PageBuilder Engine in my local environment following a PageBuilder release

Source: https://docs.arcxp.com/en/knowledge-articles/pagebuilder-engine/problems-running-pagebuilder-engine-in-my-local-environment-following-a-pagebuilder-release.html

## Symptoms

- Unable to run local environment for development immediately following the latest PageBuilder Engine release
- Running `npx fusion start` produces a variety of errors in the console
- `FUSION_RELEASE` variable is not set locally or is set to `latest`

## Cause

If you do not set `FUSION_RELEASE` or is set to `latest` , the latest release will be used which may not be compatible with your environment. For example, if your code has not been upgraded to be compatible with `4.0` , you would want to set `FUSION_RELEASE=3.X.X`. 

## Solution

1. Set the local environment variable to this: `FUSION_RELEASE=<the dev engine version you usually deploy with>` in `.env`.
2. Run `npx fusion start` again.

## More Information

[PageBuilder Engine release matrix](https://docs.arcxp.com/en/what-s-new-in-arc-xp/what-s-new-in-pagebuilder.html#UUID-c6a5bd2a-9516-03e0-7aa5-a7c6452d00ef%5FUUID-4722d5ab-903c-9027-754d-2a2c3a3a9d84)