At least the internal links to start. @axelhzf has a good point that it would be ideal to avoid 404s in our site, even if they are for outdated docs not many are looking at.

[Outdated] adding the mechanism to check

We should add an argument like --historical-apis to the link checker and only use it in CI, probably the cron job.

We want to be careful to not slow down performance too badly when implementing this. Per #496, the key is to avoid loading more files into memory than necessary.

We should process each historical API version atomically. For example, 0.44 docs should not be linking out to anything else but other 0.44 files and external links. So, we should entirely process 0.44 docs at once, then drop it from memory. Then go on to 0.43, etc.

How to fix broken links

Some of the broken links have been due to bugs in our script, like #542 and #732. Legit issues will need to be fixed via a mechanism like #719.

Update Aug 30 2024

This is high priority. We should have zero broken links for new versions of docs, meaning Qiskit 0.46+. For Runtime, aim to do all releases in 2024, but triage how bad that will be and revisit if it's going to take too much time.

Infrastructure-wise, tweak our commands to only check the targeted dev versions.