Overview
Let's assume a project where the Neos setup is just one part of a bigger setup. All building blocks are in the same Git repository, and the Neos part is in a sub-folder in that repository.
If you try to host that by simply giving the Git repository to Flownative Beach, the build will (most likely) fail very early, as the Composer manifest cannot be found.
The solution is rather simple, though…
Configuration
In the example below the Neos part of the system is in the folder packages/acme inside the Git repository.
First you need to tell the build process where the Composer root manifest is located in your repository. This is done by placing a file named .beach.yaml in your Git repository root. The content indicates the path to the Composer root manifest:
builder:
composerManifestPath: packages/acme
Using that information the build process can do what it needs to do. To be able to actually serve the result after a deployment, you need to set the instance environment variable BEACH_APPLICATION_PATH with the value /application/packages/acme in addition. This must be done in Beach in the instance details. As soon as that variable is set, your project should be up and running after the next deloyment.

In case any questions remain, contact us for support.