developers project 2025.2 Local dev session issue

[lstepany]

Hi, 

I am developing an app with the new dev projects. When I run hs project dev it now opens a hubspot page shown in the screenshot.

Has anyone enqountered this same issue? I wander if this is HubSpot's issue or am I doing something wrong?

[MuhammadAmjad]

Thanks for sharing those logs. I can see you're running into that connection issue with the new Developer Projects feature in CLI version 2025.2. This is a common problem that happens when the local dev server isn't properly establishing the session with HubSpot.

Based on what you've shown the error message indicates the CLI is trying to navigate to the project folder and run hs project dev but the connection with the Local Development Server isn't being established. Here are a few things to try.

First make sure you're authenticated with the correct account by running hs auth and verifying the account that has the developer project created. Sometimes this connection issue happens if you're logged into a different account than where the project exists.

Second try stopping any running dev servers and clearing the connection by running hs project dev stop if it's running then start fresh with hs project dev. The Local Development Server might have a stale session that needs to be cleared.

Third check if your project hsproject json file has the correct configuration especially the projectId field. If that's missing or incorrect the dev server won't know which project to connect to.

Fourth if you're behind a corporate firewall or VPN that might be blocking the WebSocket connection needed for the dev server. Try temporarily disabling the VPN to see if that resolves it.

Lastly since the Developer Projects feature is relatively new in 2025.2 there might be some environment specific issues. Make sure you're on the latest CLI version by running npm update g @hubspot/cli.

If you'd like to discuss this more in detail feel free to DM me directly.

[lstepany]

Thanks for detailed message @MuhammadAmjad ! I checked all the steps you have mentioned above and didn't get it working. Digging further...

[felixmacaspac]

Hi @lstepany it would be better if you can provide any screenshots on the logs so we can help you more with the issue you are encountering!

[lstepany]

Hi, yeah sure!
Here is all I get: 

[felixmacaspac · Accepted solution]

Hi @lstepany since it's related to the hubspot.extend issue, you should check your Settings component if its rendering it correctly with hubspot.extend

Here's an example code:

hubspot.extend<"settings">(({ context }) => <SettingsPage context={context}/>);

You can check this example in github (https://github.com/HubSpot/ui-extensions-examples/blob/main/example-2025-2-project/src/app/settings/...)

[lstepany]

Thanks @felixmacaspac . I created my app based on the github example you are refering and it was working before. At some point it stopped working.... May be I messed up my config files..

[felixmacaspac]

Hi @lstepany yup! happened to me also before, you might have messed up something along the way 😅 can you mark my answer as the correct solution if you think that solves the problem? Would definitely help others who might experience this in the future, appreciate it!

[lstepany]

@felixmacaspac   Of course I can! 😉

[Jaycee_Lewis]

Thank you @felixmacaspac 🙌