Why time zone bugs are usually a testing problem, not a data problem
Most time zone bugs do not come from bad data. They come from code that was never tested against the one week a year when the rules actually change.
Tag
#time-zone
The trouble with data that's accurate on launch day only
A dataset announced with pride and never revisited degrades quietly. Borders shift, postal systems change, and time zone rules get amended by governments that do not send a press release.
Open time zone data should not be a premium feature
Time zone lookups run on a public, actively maintained data source. Charging a separate premium for that lookup does not reflect a real added cost.