The risks with 6.99 being a development branch is “understood” and “acceptable”. I put the understood and acceptable in quotes because it isn’t possible to do.
Has anyone taped out a board with 6.99? Close to taping out? Any gotchas?
If one starts a design in 6.99, based on what is known now, what is the likelihood a project developed and taped out in a month will be upgradable to the release version in a year?
If I have a project in 5.1.8, can I open it directly in 6.99 or do I have to open it in 6.0.x and then 6.99?
There are some really great features in 6.99 and I’m a big believer in testing the development versions.
A later version can most probably open your design. It’s possible that at some point in the nightly builds there is a bug in the file format or when a file is saved, and in that case compatibility is not guaranteed. But is it likely? Not very. If the file can be opened successfully with the then-current development version after the last modification to your project, the later KiCad versions should be able to open it. You can do your project and after it has been finished, open it a couple of times with later KiCad development nightly builds, say, within some weeks. If it’s OK, it’s very unlikely that a later stable version couldn’t open it.
Even if there’s a file save bug — I’ve been bit by that before sometime during the 5.99 phase, and I’ve never seen this be something you can’t fix with a little clever poking around in a text editor.
Using a x.99 for “real” boards is definitely for the adventurous, but I’ve never heard of it ending in disaster. I say go for it!
Or if you don’t have that kind of skills, you can attach the project here and someone will be willing to do that for you, just as a return for you being adventurous and helping the development with bug reports.
The chip designers whose machines I used to adminster still talked about tape-out milestones (kmstones?) when Internet uploads has been the practice for decades.
Same here. Always using nightlies litterally since years. Hardly any real showstopper that blocked me longer than a day or so. Admittedly hobbyist use though.
I’ve been using nightlies for the past 2 years and never faced big problems.
The only exception would be the occasional crash on some versions and once I had a file that would crash pcbnew immediately. I rolled back the KiCad version to a nightly a few weeks before and reported the bug, it was fixed within a few days (kudos to the dev team!).
I’d only warn that when colaborating with other people, this gets trickier - older versions might not open the most recent file format.
I used v5.99 last year for my job, never had an issue not solved by dev team longer than 24 hours . I have started using v6.99 only two days ago because It become really unstable after v6.0 release. After using for 1.5 working day, faced no show stopper issues. Currently working on schematic only. I think now v6.99 is as good as v5.99 was
Mind you I find it strange that seemingly unconnected features that have not been upgraded often seem to develop bugs in the nightlies, SVG imports being a classic case , work fine in V6 release got buggy around Feb in the nightlies
Yep, this is a first time I put a project inside repository, to try how it works. But not my library, stupid me
Also, one needs to remember hitting commit from time to time, othervice repo is useless (I am trying to build some good habits, git’ing is relatively new for me)
. I have started using v6.99 only two days ago because It become really unstable after v6.0 release. After using for 1.5 working day, faced no show stopper issues. Currently working on schematic only. I think now v6.99 is as good as v5.99 was 
