Hello Murat!

Please check if you have a package.json with the script called "start" in your project. Depending on the nx version you used you might not have it there.

The script should be:

"start": "nx serve"

If you want to run all the projects in the same repo then you can use: nx run-many --target=serve

Code reference: https://github.com/makinhs/nestjs-graphql-medium/blob/main/package.json

Hope it helps,

Cheers