Ask HN: Tools of the Trade, 2019 Edition

Almost a decade ago, Joshua Schachter started this thread on HN for discussing hosted useful services: https://news.ycombinator.com/item?id=1769910

> When I first started delicious, we had to host most of the services ourselves. CVS, mail, mailing lists, etc etc etc.

> These days, lots of that stuff is available as SaaS. What are the tools and services people use instead of hosting their own?

What do we have now in 2019?