Onboard devs in company

How does everyone ramp-up employees, more specifically devs in their company?

I have seen this to be a repetitive problem. The wikis and notions work but providing a structured way to onboard is missing.
Do you guys have these problems too? Any tools?

I wrote an article for a hack i tried:
https://medium.com/gramoday/i-found-a-hack-y-way-to-onboard-new-joiners-dd2ec8c201f7