I'd suggest to put all issues in main project. OneDev has no problem linking issues in parent project in commits of child projects. Also latest OneDev version allows to define a short project key, so that issue referencing from other projects can be done via a short issue key: (check https://onedev.io/blogs/7 for details)

Closing. I was surprised that cross-project linking was not available. It felt like it would make sense if it was. Thank you for your reply.

I was surprised that cross-project linking was not available

What do you mean for cross-project linking? Commits can reference issues created in other projects without any problems.

Coming from Azure DevOps, I thought it made sense to have have User stories / Epics in my main project and link them to issues in the child projects. As a product owner I thought could then create a User story "User sends diagnostics data to api, so that developer can...." in a main project. From here I could then manage the user story by being linked to two issues - one in the private backend project and another issue in a public frontend project.

I think my reasoning came from being used to another devops system. One where I only worked with a single repository with everything in it. I just had to realign with OneDev.io and working with multiple projects/repositories

In order words I'm fine with the best practise suggestion you offered. Commits to child projects will be visible in the main project issue if I tag the commits with the issue key and number. This is fine.

However I think project managers and product owners will probably lean towards DevOps like Azure or Jira. As a product owner I would, but as a open source developer I lean towards OneDev.io and I'm going to spend more time programming than organizing work items.

Thanks for the elaboration. This is totally possible in OneDev. Issue types, fields and links are fully customizable. You may configure an issue type "Epic" and add epics in main project, and link with other issues defined in child projects. For details of how issue links work, please check this tutorial.

OneDev designs to be flexible, and you may choose the way you feel most comfortable, whether split work in multiple projects, or put them in a single project.

Want to mention that when link to issues in other projects in an issue, the project part of issue reference needs to be specified, for instance main/ui#100, or simply UI-100 if you specified project key as UI for main/ui.

Yeah, that works. Following the guide and creating an "Epic" (DUV-8) issue in parent project and a "User story" in a child project. I can definitely link those together if I write the User story issue manually. It didn't seem to suggest it before I wrote it "UI-19" in the parent project

I think this is very powerful. I also teach programming (and the surrounding aspects like agile, Linux and server hosting). My students usually rely on GitHub, but GitHub is confusing (and bloated compared to this). OneDev seems straight to the point with both Git and CI/CD, and they can set one up themselves and play around with it with discretely and comfortably. I noticed you been asking for testimonials - I might submit one when I've become more familiar with it.

Thanks for willing to provide testimonials. That will be very helpful.

As to link issue suggestion, by default, it only suggests issues in current project. However when you input key of other projects, for instance UI-, OneDev will then start to suggest issues in that project, and you can continue to type part of issue title to filter the results.

Want to mention that when link to issues in other projects in an issue, the project part of issue reference needs to be specified, for instance main/ui#100, or simply UI-100 if you specified project key as UI for main/ui.

Sorry for hijacking the issue but I have a question for it (more towards using IDs for in cross-project commits). I assume that the reference is the one displayed in the issue sidebar (In this case it's quite simple as "OD-1909" but it can have parent project). But - the address of the issue is https://code.onedev.io/onedev/server/~issues/1909 (notice only number 1909) but reference and in the top breadcrumb we also have reference including OD- prefix. How is this prefix configured? The project name is server with parent onedev (thus onedev/server/).

I assume this was introduced in OD-1883 ?

Hello The prefix is configured by heading to General Settings of a project. Enter at least two letters in the Key box right below the required project name. It's the second textbox in the General settings.