@AshesOfOwls, hi!
When a project is hosted in Github ( or Gitlab or bitbuck, etc...), only the project owner and the maitainers will be permission to commit, push and merge code. The fact of the source code is open in the internet isn't the problem. The real problem a weak process. The developer process needs code review, continuous integration, etc...
Even if the code is new, the community can contribute!
But I understand if the team consider that now isn't the moment. In this case, is yet necessary to push the source code in a repository. In Gitlab, Github and Bitbucket is possible to create a team with private/internal source code. They will help to implement a good development process.
I could, for example, set up an Ignition 5 homologation environment, where the React frontend would be exposed in a gitlab / github pages. It could also be configured to run unit tests and require that pull/merges requests would only be accepted if successful. What I said here you already know, but I'm just reinforcing :D
I was on this forum even before Ignition 1. I spent a long time out and came back now. I am surprised that there were 4 Ignition. Could you tell me what happened out of curiosity? It could be a link to a forum topic.
Ok, as the frontend is React, it's possible to publish it in any static server (nginx, apache). A hosting free alternative is to publish in the github/gitlab pages.
Graphql enables to transfer data between backend and frontend as minimum as possible. This is a good point. Less network trafic, less money necessary in infrastructure.
I confess that I did not work with graphql and apollo. Who performs the queries is the Apollo server? What's the database, Postgres? Is there no Django / Rails / Laravel / Spring boot application?
Great!
Just be careful not to be too picky with yourself and thus take a long time to share the project with other developers. If you define specific tasks, developers will be able to contribute. Examples:
Search component
List component
...
CI to tests
CI to build code
Configure Storybook
So, I believe, those who are used to software development can already contribute. And, when this initial part is done, newer / enthusiastic programmers will also be able to contribute when you share the knowledge.