Timedates are hard, and units may require even harder historical/present "political" tracking as how they are defined, and I would never want to maintain this kind of dependency: https://github.com/ryantenney/gnu-units/blob/master/units.da...
And what comes to timedate problems, I try to keep it simple if the project allows: store and operate with UTC timestamps everywhere and only temporarily convert to to local time (DSTs applied, if such) when displaying it in user-facing UI. This functionality/understanding can be locked into own 20-line microlibrary-dependency, which forces its responsible person to understand country's timezone and when e.g. DST changes and where/how/who decides DST changes and what APIs is used to get UTC time (and of course, its dependencies, e.g. NTP, and its dependencies. e.g. unperturbed ground-state hyperfine transition frequency of the caesium-133 atom, which result is then combined with the Pope Gregory XIII's Gregorian calendar, which is a type of solar calendar mixed with religious event for fixing the time, which which is then finally corrected by rewinding/forwarding "the clock" because its too bright or dark for the politicians).
I would still rather using a library for dates, a million times so.
Yes, I agree with this
> The self-written one is maintained by 1 person, the other is used by 100+ people who could jump in a collaborate on its fixing.
Libraries that have 100 people collaborating on it are very few
Most likely you'll have to vendor it and fix whatever issues you have.
Even worse when it's a dependency of a dependency and you also use it, so, let's say a dependency of yours bumps the version but this breaks your code. (Not sure this breaks only in python or in js as well, but it's possibly that it does)
I can’t for the life of me figure out why. If you update everything incrementally you bypass the upgrade version problem when you’re so far behind that so much has changed that it becomes an overwhelming burden.
I think frozen dependencies are a big anti pattern, and places where I work that regularly update their deps tended to have better software practices generally