I'll be forever grateful to djb for djbdns. In the early 2000s in the dot com boom I was CTO for a domain registration and hosting company. We had millions of

I'll be forever grateful to djb for djbdns. In the early 2000s in the dot com boom I was CTO for a domain registration and hosting company. We had millions of DNS records to host and at the time we were using bind. It used to take 45 minutes to reload on the fastest machines we could get with rocket class SCSI disks and the servers used to run with a massive load average. Eventually I discovered djbdns which was great on so many fronts. It had a nice single file text format which was very easy to build from the database. That file was digested into a read only database which djbdns served directly, and best of all you could swap databases with zero downtime. This turned reloading the nameservers into something which would run in a few seconds and the DNS servers then ran with minimal load. You'd make different choices today most likely, but it really saved our bacon back then!