I had no idea travel was this difficult for people who aren't EU citizens.
Wow, I'm almost annoyed on the authors behalf of how much hoops there are to jump through.
>To apply for British citizenship, you need to prove you were physically in the UK on your application date but five years ago. Not approximately five years, not that week—that exact day when you press "submit" on the form minus five years. Miss it by 24 hours and your application is reject after months of waiting, and you have to pay a hefty fee to re-apply.
That's a hilarious requirement. I wonder how that ended up in there.
First, the author is actually wrong. The date is not 5 years before you submit, but is 5 years before the form is received by the home office! So there are a few days of uncertainty, depending on how fast Royal Mail was with the physical documents.
Additionally, I did a request for my information from the home office prior to filling in my form. After all, you have the right to request the information they have on you that will be used to verify your form. Kafka would be proud.
Let me tell you, Home Office doesn't have a clue where you were 5 years ago. It had approximately 50% of my trips, and frequently only had only one leg of the journey. Plane, ferry, train, sailboat, ... it didn't matter. It seems like they have not been keeping the information very well.
> It had approximately 50% of my trips, and frequently only had only one leg of the journey
Relevant current news: Home Office denying child benefits to 1000s of people because they had incomplete data of people vacation trips, so people were thought to have emigrated and never returned [0]. Some people who never even left (due to cancelled flights, denied boardings etc.) were also affected.
As someone who's been through that dance twice, it's 5 years from the time (well, day) you press "Submit" if you're applying online, or $RANDOM days of Royal Mail nonsense if you choose to apply by post.
I agree though, the Home Office doesn't have a way of knowing where you were fore sure 5 years ago unless they got someone to go through your "days in and out of the UK" list and vetted/cross-referenced it. And even then it'd likely be incomplete and they'd have to guess.
My surmise is that they look at the level of effort you've put in to filling out that detail, and if the total days in/out isn't particularly a borderline case, then they just wave that bit through.
I would have thought that the point is that you're supposed to be there continuously for some considerable duration (and having worked through other processes of legal immigration) before applying for citizenship.
So the idea of trying to figure out exactly which day five years in the past you have to mention seems odd to me. If there's really no care being paid to the intervening time... well if you're trying to exploit a loophole like that I think I'd prefer that it's difficult... ?
Too bad there aren't too many people in their 90s around to discuss how things operated prior to WWII. Schengen was a solution to a problem that had only been created a few decades earlier.
Most of those work restrictions are put in place to protect local labor. They just don't want tourists taking jobs from locals in tourist places without a permit, and without paying taxes.
They really don't care much you're doing remote work for a corporation in California or writing a book.
Last time I looked was a few years ago, but I was surprised how hard it was going to be to legally live in France while keeping my US tech job. My employer was happy to do what they had to to make it happen, but there just didn't seem to be a route in the French immigration system.
The options seemed to be:
- Get a job in France and get a work visa. This is very difficult due to economic protectionism.
- Come on a tourist visa and not work.
- Be provably independently wealthy and get some variety of golden visa. This meant proving that you had enough assets to live (lavishly I might add) long term without working.
No easy option for "I want to come to your country, get paid USD by a US company, but pay taxes to you!"
I think there have been some new developments regarding digital nomad visas since then. Still, seemed crazy given what a good arrangement it would have been for France.
> I called the app Residency and you can get it here. No subscriptions, costs less than an airport martini, and you'll likely regret it less a few hours later.
The article is content marketing, so I wouldn't be surprised if the pain points are being talked up somewhat (but who knows?)
Anecdotal evidence: timezone-aware precision might be only necessary for those pushing it to very edge of the allowances, but travel log spreadsheet was very very real for me, and everyone else in my own immigrant bubble. I still have it somewhere.
UK officials seem to operate on vibes though, not obsessive precision - I witnessed missed presence days being successfully propped up with a good sob story, but I can imagine it still being useful if you need to appeal a case where vibe turned against you.
Then was a short rest between making oath and Brexit, and here we are at that shit again - spreadsheet is back, and there's a script for Schengen rolling days.
Guessing it stems from "we need something dead-simple to evaluate that yields a definite yes-or-no answer, with no annoying variables."
I'm trying to think of some other reason they might want a specific moment rather than "pick your own instant within this span", but I can't think of anything. Even if it was to "make sure you aren't claiming the same time on two applications to different places", the person could have simply staggered the applications.
The other reason is more mundane. There's been a lot of political incentive to reduce immigration for a long time, which means adding arbitrary friction to increase the effort of applying and decrease the number of successful applicants.
Whether this is _effective_ is a different question, but certainly it's gotten a lot harder in recent decades, even pre-Brexit.
My guess is that if you need to have been there for 5y, you need to have a way to tell when that 5y starts. I presume it only matters if you apply the day after 5y. When I applied I had been in the UK for over 10y, provided 10y worth of proof of address, and the issue never came up.
It's not even hard really, I did it lastyear. I book a visit to the city hall, they look into the address db and see when I registered the first time. I see exactlt the same thing myself when I login into the thing.
The official agrees with me on the appointment date to actually submit the application, that is after cutoff date.
I put a signature on one sheet of paper, pay a thousand and go my way. The thing takes 15 min tops.
It depends on where you're going and what you're doing.
A lot of this faff isn't relevant if you're not applying for any visas or citizenship. Which is most people, most of the time.
The obvious solution to most of these problems for most people is "don't cut it close to any of the limits". If you enjoy traveling a lot, that's definitely a problem, but most people don't cross borders often enough to run into this many corner cases.
This is only a small peek into the awful bureaucracy that will hit Europe if extreme right wing parties keep gaining popularity across the EU. The extra calculations Brexit imposes, but not for every country you travel through!
The point is not to produce a system where a software engineer can loophole the system. The point is to try to prevent people who aren't committed to the UK apply for citizenship.
Convoluted rules like that smack of the ridiculous literacy tests for voting in the US during the Jim Crow era (if you don't know why the terms “grandfathering” and “grandfather clause” have fallen out of fashion in recent years, go have a poke around that bit of history which is where those terms originate).
Either that or it looks like a dysfunctional overly-complicated system like the mechanisms draw by Heath Robinson, which while better still isn't good. How many good (morally) and useful (i.e. to the economy) people are being rejected because of unnecessary complications like this?
> To apply for British citizenship, you need to prove you were physically in the UK on your application date but five years ago.
I am confused whats British citizenship application to do with his, or any travel at all? That's not what you do regularly, I mean most people do not apply for citizenship in other countries ever in their lives? Or am I missing something?
> I had no idea travel was this difficult for people who aren't EU citizens.
I traveled before and I traveled after Schengen and the only thing that changed was not having to wait a bit at border control. What the article describe concerns a very small number of people, and exist only because of cheap air travel and internet
Right now the biggest problem in life is the country of my passport.
I have enough in savings and enough passive income to be able to live comfortably almost anywhere, but whenever I talk to travel agents, or people who can help set up companies etc in the countries I want to go to, first they're like "Sure, we can do it, when do you want it" etc and then they ask where I'm from, and when I tell them, they either stop replying or say sorry, they can't help me.
sigh...Racism is a funny thing. They haven't even seen me, or seen my history of travel, or anything, they just stop cooperating when they see that one word, the name of my country.
And I can't blame them either, I know many people from here go and overstay there visas and generally make problems in other countries.
I just wish I could put down a deposit of a few thousand dollars as a guarantee that I'll behave and get a visa.
But it is a ridculous requirement. Like having a millsecond-hand one a pendulum clock it appears to be to precise for the timeframe involved
Why not just make it a before-date if you care for someone having been here for a time? So just proof that you have been here X years ago or longer. Totally sufficient and much easier to have at hand.
But this is of course the point. It isn't policy where the state requires a certain thing and all people who fulfill the requirement have a shot. Instead the state makes the process of demonstrating the requirement hard on purpose as a means of reducing the people who get the benefit.
And this idea isn't just unique to the described process. It is everywhere. A bit of friction in certain places is placed there on purpose and it can also be a net positive for that friction to exist. But beyond a certain level it can turn people with rights into beggars.
This is about all the country-specific requirements for tax residency, visas, citizenship, etc.
But I don't know what downloading a border means. The title makes it sound like this is going to be about downloading national mapping data... If the author was looking for an evocative metaphor, I don't think this one works. Maybe it's supposed to refer to:
> It would be alright with a single source of truth, but all these facts are scattered across (semi)official websites and PDFs, and you're supposed to figure it out yourself.
But they got those all through... downloading. I.e. cURL.
Few of my relatives just went to Europe as tourists, threw away their back home tickets and went illegal. After few years they legalised and now citizens. And I'm still here, because I don't want to break the law and I don't have valid legal grounds to get the working visa. It sucks to obey the law.
This is such a common thing and tolerated you have to wonder whether it's actually immoral. I've met many people on my travels who went to Europe on tourist visas, got work and then got to stay legally later. No one was deported.
All of these were people in low-paying services industries, jobs Europeans don't usually want (waiters, cleaners, etc).
The only ones that had issues with immigration were my qualified worker friends who got a work visa and then the company had layoffs while they were there, losing their sponsorship. People with masters degrees who had to scramble to find new work in 30 days or face deportation.
It's hard not to think that's intentional.
I have a nuanced opinion because it's a rather complex subject but it's just a weird thing to have seen happen. As a tourist I had to prove up and down I wasn't going to stay there only to see no one else cares outside the airports. There's obvious wage suppression going on with these policies but these waiters and cleaners also had college degrees from good institutions, probably more qualified than some citizens.
> I've met many people on my travels who went to Europe on tourist visas, got work and then got to stay legally later.
That's completely legal for some nationalities, at least in Germany. §41 AufenthV allows people from certain countries to come to Germany and apply for a visa there.
A separate paragraph allows people to convert a tourist visa to a residence permit if the reason for the residence permit appeared while they were visiting. For example, going through rounds of interviews, and being offered the job while you're visiting Germany as a tourist.
There are so many other paths, but navigating those options can be confusing.
Borders of countries are fundamentally human constructs. There is no morality associated with crossing them legally or illegally. This is the difference between a law declaring something illegal because they think it is better for society (a parking ticket, say) and a law created that require moral turpitude (murder, say).
What do you mean by valid legal grounds? For many countries all you need is to get a local job paying above a threshold, that’s enough to get a work permit.
You need a work permit to get a job, not the other way around. If you meant a "job offer", yes you can get a work permit with a job offer, but not everybody is that lucky.
If you are on a tourist visa you can't legally get a job then worm your way to a valid work/residency visa. I mean you can, just not legally.
The exact country isn't clear, it depends from country to country. Spain for example have "arraigo social", where I think if you've stayed for 3 years (illegally/legally) and can demonstrate you've ended up in some sort of "link" with Spanish society (like having a permanent job) you can apply for a "temporary residence and work permit". Once you have that, you're legal and you could apply for permanent residence and eventually citizenship, granted you fulfill those requirements.
I have a bunch of friends, with jobs ranging from bartenders to software developers, who've successfully were allowed to stay in the country after doing things that way, initially staying illegally and later regularized their situation.
Huge respect to the author for the details that have gone into this. I'd spent a week hammering at a Claude max 20x plan to try and build schengen 90/180 rolling window + tax residency in a couple of countries tracker... and that was hard work. I can only imagine how much effort has gone into this, to get all the details right.
It's unclear whether the author wrote all of this themselves, or if they outsourced a bunch of it to Claude. My experience with Claude was that it was terrible at writing code to do the math, even when I explained what the calculation needed to be, what the input was, and what the expected result was. It ultimately took starting a whole new project just to do the rolling window calculation, and then have that fed back in.
My biggest question for the author, if they happen to see this, is: how much manual testing validation did you do of the outputs the app produces? IE: Did you do the inputs + transformations = output calculations yourself as well, counting days on calendars, etc, to validate that the app is actually accurate? (That was the only way I developed any faith in solution I made for myself, which is way less impressive than your app). Regardless of whether you wrote the code yourself or not, a thorough test harness feels vitally important for an app like this.
I tend to find that for things like this that are really math heavy, it's usually better to create a DSL (or create easily readable function calls, etc) that you can easily write yourself instead of relying on AI to understand math heavy rules.
Bonus points, if the rules are in an easily editable format, you can change them easily when they need to. It seems that was the path the author took...
And yes this kind of use-case is exactly where unit tests shine...
> create a DSL (or create easily readable function calls, etc)
These aren't really that different. Consider the history of the earliest (non-assembly) programming languages, particularly https://en.wikipedia.org/wiki/Speedcoding , as well as the ideas expressed by Lisp.
I do the opposite, set up everything myself in terms of architecture/design of the software, so the AI can do the boring boilerplate like "math heavy rules". Always interesting to see how differently we all use LLMs.
When I’ve worked on complex scheduling problems like that I use copious unit tests, they’re perfect for this kind of input->algo->output problem where algo has tons of edge cases.
Indeed, not using unit tests and instead trying to manually test all the cases sounds crazy to me!
I'm not sure I’m reading this right but are you saying that an AI made you dumber and then you complain that the AI is too dumb? That sounds like a lose-lose deal tbh.
I'm sorry. I don't want to fight here, but you have literally just said you paid Claude to do the thinking for you (except for some math), yet you're talking about this like you're some kind of scientist; or that you've done this extensive, in-depth work.
You made an AI vibe-code an app in a week and now you're impressed someone else was able to do it better?
Am I missing something? Is it maybe just your writing style that makes it come across so "from your high horse"?
This task seems like something a competent Excel user could create. I think the hard part is knowing the rules and the corner cases than any of the "math" (just addition and subtraction, surely) required.
I just realized this was the same author who made the apple watch integration for their gym entry system, I loved their writing then, and I loved it here!
Regarding the writing, I'm the opposite.. but I can't point out why I don't like it.
Maybe because the author is trying to sound sleek and sexy, "look at me, jetset international traveller", although the topic is so nerdy and dull, and the bragging feels off-putting to me.
(My opinion. Did I need to share it? probably not. Flag away if you think so)
I'm a PureGym member. I just memorised the 8 digit number that never changes and I input it manually. It takes seconds. I agree that the official app is garbage. I just don't want or need to get my phone out at all.
Ah, the classic programmer's mistake of treating complicated human interaction systems as a computer programs.
There is no State Almighty judging you to the last dot of absurdly complicated rules (well, in 99.99% cases when you don't actively look for trouble). Like, if you overstayed Schengen visa for one day because you messed up with counting entry and exit days, but used it otherwise for its intended purpose, the border officer likely won't even notice. Or for tax residence, a lot of countries I know just take what you say about your trips at face value - especially when there is no way to check it.
Just relax. If you don't know how to count your days in Morocco because they changed the time zone in an inconvenient moment, the officer evaluating your documents doesn't know that too. It's truth and best effort that counts.
I've heard many stories of people overstaying their visa in the US by e.g. one day, by way of a mishap or honest mistake, and subsequentially being denied visas or turned away at border control. The effects of this can go on for years and years... it's basically zero tolerance
I overstayed my visa by a week in Thailand couple of decades ago because the task I was sent out to perform took longer than expected. I just had to pay a reasonable fine on exit that I then claimed back on my expenses. There was certainly not even a suggestion that I would be unwelcome in Thailand in the future.
Overstaying a visa is a big deal. You should not be counting days or nights because you should not let yourself be in the country anywhere near the expiry of a visa.
> You should not be counting days or nights because you should not let yourself be in the country anywhere near the expiry of a visa.
You're privileged if you're able to do so. In many occasions people have single-entry visas with one day leeway from tickets submitted to the consulate.
For USA, A Visa is a right to request entry into the country. The I-94 defines the duration you are authorized to stay. You can have an expired Visa and time left on you I-94 and remain in the country.
>Like, if you overstayed Schengen visa for one day because you messed up with counting entry and exit days, but used it otherwise for its intended purpose, the border officer likely won't even notice.
When that wasn't automated that might have been the case (not that its a good thing).
It's certainly not the case now that there is literally an API that tracks that.
Enforcement is arbitrary and vibes based, but only if you broke a rule. If you didn't break a rule they find it much harder to punish you, no matter what the vibes are. But also if you have good vibes you might not get punished no matter what rules you broke.
Readit News
Wow, I'm almost annoyed on the authors behalf of how much hoops there are to jump through.
>To apply for British citizenship, you need to prove you were physically in the UK on your application date but five years ago. Not approximately five years, not that week—that exact day when you press "submit" on the form minus five years. Miss it by 24 hours and your application is reject after months of waiting, and you have to pay a hefty fee to re-apply.
That's a hilarious requirement. I wonder how that ended up in there.
Additionally, I did a request for my information from the home office prior to filling in my form. After all, you have the right to request the information they have on you that will be used to verify your form. Kafka would be proud.
Let me tell you, Home Office doesn't have a clue where you were 5 years ago. It had approximately 50% of my trips, and frequently only had only one leg of the journey. Plane, ferry, train, sailboat, ... it didn't matter. It seems like they have not been keeping the information very well.
Relevant current news: Home Office denying child benefits to 1000s of people because they had incomplete data of people vacation trips, so people were thought to have emigrated and never returned [0]. Some people who never even left (due to cancelled flights, denied boardings etc.) were also affected.
[0] https://www.theguardian.com/politics/2025/nov/01/hmrc-likely...
I agree though, the Home Office doesn't have a way of knowing where you were fore sure 5 years ago unless they got someone to go through your "days in and out of the UK" list and vetted/cross-referenced it. And even then it'd likely be incomplete and they'd have to guess.
My surmise is that they look at the level of effort you've put in to filling out that detail, and if the total days in/out isn't particularly a borderline case, then they just wave that bit through.
So the idea of trying to figure out exactly which day five years in the past you have to mention seems odd to me. If there's really no care being paid to the intervening time... well if you're trying to exploit a loophole like that I think I'd prefer that it's difficult... ?
Newer generations don't get how lucky they are to have been born into EU, appreciate it while it lasts.
Nations can sign Schengen, but are never forced to join the EU, nations can be EU members but are allowed to refuse the Schengen treaties.
I get how lucky I was for 25% of my life expectancy.
Most people can't afford to travel to the Schengen Area for more than the visa-free limit of 90 days within a 180 day period.
Those that can are "digital nomads" and are almost certainly working illegally while travelling.
The options seemed to be:
- Get a job in France and get a work visa. This is very difficult due to economic protectionism.
- Come on a tourist visa and not work.
- Be provably independently wealthy and get some variety of golden visa. This meant proving that you had enough assets to live (lavishly I might add) long term without working.
No easy option for "I want to come to your country, get paid USD by a US company, but pay taxes to you!"
I think there have been some new developments regarding digital nomad visas since then. Still, seemed crazy given what a good arrangement it would have been for France.
Except few countries, all EU countries tolerate this
> Those that can are "digital nomads" and are almost certainly working illegally while travelling.
WTF are you talking about? The Schengen Area is right here and you don't need a visa to work anywhere else in it. That's the whole point.
The article is content marketing, so I wouldn't be surprised if the pain points are being talked up somewhat (but who knows?)
UK officials seem to operate on vibes though, not obsessive precision - I witnessed missed presence days being successfully propped up with a good sob story, but I can imagine it still being useful if you need to appeal a case where vibe turned against you.
Then was a short rest between making oath and Brexit, and here we are at that shit again - spreadsheet is back, and there's a script for Schengen rolling days.
I'm trying to think of some other reason they might want a specific moment rather than "pick your own instant within this span", but I can't think of anything. Even if it was to "make sure you aren't claiming the same time on two applications to different places", the person could have simply staggered the applications.
Whether this is _effective_ is a different question, but certainly it's gotten a lot harder in recent decades, even pre-Brexit.
The official agrees with me on the appointment date to actually submit the application, that is after cutoff date.
I put a signature on one sheet of paper, pay a thousand and go my way. The thing takes 15 min tops.
But it's continental Europe, not UK
A lot of this faff isn't relevant if you're not applying for any visas or citizenship. Which is most people, most of the time.
The obvious solution to most of these problems for most people is "don't cut it close to any of the limits". If you enjoy traveling a lot, that's definitely a problem, but most people don't cross borders often enough to run into this many corner cases.
This is only a small peek into the awful bureaucracy that will hit Europe if extreme right wing parties keep gaining popularity across the EU. The extra calculations Brexit imposes, but not for every country you travel through!
That’s true for many, but my passport isn’t very strong, so I still have to deal with a lot of paperwork for most transits.
Convoluted rules like that smack of the ridiculous literacy tests for voting in the US during the Jim Crow era (if you don't know why the terms “grandfathering” and “grandfather clause” have fallen out of fashion in recent years, go have a poke around that bit of history which is where those terms originate).
Either that or it looks like a dysfunctional overly-complicated system like the mechanisms draw by Heath Robinson, which while better still isn't good. How many good (morally) and useful (i.e. to the economy) people are being rejected because of unnecessary complications like this?
I am confused whats British citizenship application to do with his, or any travel at all? That's not what you do regularly, I mean most people do not apply for citizenship in other countries ever in their lives? Or am I missing something?
I traveled before and I traveled after Schengen and the only thing that changed was not having to wait a bit at border control. What the article describe concerns a very small number of people, and exist only because of cheap air travel and internet
Note also that this isn't a travel requirement.
I have enough in savings and enough passive income to be able to live comfortably almost anywhere, but whenever I talk to travel agents, or people who can help set up companies etc in the countries I want to go to, first they're like "Sure, we can do it, when do you want it" etc and then they ask where I'm from, and when I tell them, they either stop replying or say sorry, they can't help me.
sigh...Racism is a funny thing. They haven't even seen me, or seen my history of travel, or anything, they just stop cooperating when they see that one word, the name of my country.
And I can't blame them either, I know many people from here go and overstay there visas and generally make problems in other countries.
I just wish I could put down a deposit of a few thousand dollars as a guarantee that I'll behave and get a visa.
Why not just make it a before-date if you care for someone having been here for a time? So just proof that you have been here X years ago or longer. Totally sufficient and much easier to have at hand.
But this is of course the point. It isn't policy where the state requires a certain thing and all people who fulfill the requirement have a shot. Instead the state makes the process of demonstrating the requirement hard on purpose as a means of reducing the people who get the benefit.
And this idea isn't just unique to the described process. It is everywhere. A bit of friction in certain places is placed there on purpose and it can also be a net positive for that friction to exist. But beyond a certain level it can turn people with rights into beggars.
Dead Comment
If that's the first thing he thinks of while transiting through a UK airport, he deserves a citizenship, no questions.
This is about all the country-specific requirements for tax residency, visas, citizenship, etc.
But I don't know what downloading a border means. The title makes it sound like this is going to be about downloading national mapping data... If the author was looking for an evocative metaphor, I don't think this one works. Maybe it's supposed to refer to:
> It would be alright with a single source of truth, but all these facts are scattered across (semi)official websites and PDFs, and you're supposed to figure it out yourself.
But they got those all through... downloading. I.e. cURL.
> You can't cURL a border. But you can track your own state carefully enough that when the governments know the answer, so do you.
Maybe API would be a better term, but it's a clever.
All of these were people in low-paying services industries, jobs Europeans don't usually want (waiters, cleaners, etc).
The only ones that had issues with immigration were my qualified worker friends who got a work visa and then the company had layoffs while they were there, losing their sponsorship. People with masters degrees who had to scramble to find new work in 30 days or face deportation.
It's hard not to think that's intentional.
I have a nuanced opinion because it's a rather complex subject but it's just a weird thing to have seen happen. As a tourist I had to prove up and down I wasn't going to stay there only to see no one else cares outside the airports. There's obvious wage suppression going on with these policies but these waiters and cleaners also had college degrees from good institutions, probably more qualified than some citizens.
That's completely legal for some nationalities, at least in Germany. §41 AufenthV allows people from certain countries to come to Germany and apply for a visa there.
A separate paragraph allows people to convert a tourist visa to a residence permit if the reason for the residence permit appeared while they were visiting. For example, going through rounds of interviews, and being offered the job while you're visiting Germany as a tourist.
There are so many other paths, but navigating those options can be confusing.
If you are on a tourist visa you can't legally get a job then worm your way to a valid work/residency visa. I mean you can, just not legally.
I have a bunch of friends, with jobs ranging from bartenders to software developers, who've successfully were allowed to stay in the country after doing things that way, initially staying illegally and later regularized their situation.
It's unclear whether the author wrote all of this themselves, or if they outsourced a bunch of it to Claude. My experience with Claude was that it was terrible at writing code to do the math, even when I explained what the calculation needed to be, what the input was, and what the expected result was. It ultimately took starting a whole new project just to do the rolling window calculation, and then have that fed back in.
My biggest question for the author, if they happen to see this, is: how much manual testing validation did you do of the outputs the app produces? IE: Did you do the inputs + transformations = output calculations yourself as well, counting days on calendars, etc, to validate that the app is actually accurate? (That was the only way I developed any faith in solution I made for myself, which is way less impressive than your app). Regardless of whether you wrote the code yourself or not, a thorough test harness feels vitally important for an app like this.
And yes this kind of use-case is exactly where unit tests shine...
These aren't really that different. Consider the history of the earliest (non-assembly) programming languages, particularly https://en.wikipedia.org/wiki/Speedcoding , as well as the ideas expressed by Lisp.
Indeed, not using unit tests and instead trying to manually test all the cases sounds crazy to me!
Deleted Comment
I'm sorry. I don't want to fight here, but you have literally just said you paid Claude to do the thinking for you (except for some math), yet you're talking about this like you're some kind of scientist; or that you've done this extensive, in-depth work.
You made an AI vibe-code an app in a week and now you're impressed someone else was able to do it better?
Am I missing something? Is it maybe just your writing style that makes it come across so "from your high horse"?
https://drobinin.com/apps/residency/
If I wasn't on android and decidedly sedentary at the moment, I'd love to see how it works.
https://news.ycombinator.com/item?id=44910865
Maybe because the author is trying to sound sleek and sexy, "look at me, jetset international traveller", although the topic is so nerdy and dull, and the bragging feels off-putting to me.
(My opinion. Did I need to share it? probably not. Flag away if you think so)
Digital nomads gonna digital nomad…
There is no State Almighty judging you to the last dot of absurdly complicated rules (well, in 99.99% cases when you don't actively look for trouble). Like, if you overstayed Schengen visa for one day because you messed up with counting entry and exit days, but used it otherwise for its intended purpose, the border officer likely won't even notice. Or for tax residence, a lot of countries I know just take what you say about your trips at face value - especially when there is no way to check it.
Just relax. If you don't know how to count your days in Morocco because they changed the time zone in an inconvenient moment, the officer evaluating your documents doesn't know that too. It's truth and best effort that counts.
I've heard many stories of people overstaying their visa in the US by e.g. one day, by way of a mishap or honest mistake, and subsequentially being denied visas or turned away at border control. The effects of this can go on for years and years... it's basically zero tolerance
Anywhere else, less strict. Still can be problematic yes. And of course depends on the circumstances
Why is the US so awkward?
Instead, arrive a bit early to the airport, and analogously, don't run visas down to the last hour based on the minutiae of Moroccan timezones etc.
You're privileged if you're able to do so. In many occasions people have single-entry visas with one day leeway from tickets submitted to the consulate.
When that wasn't automated that might have been the case (not that its a good thing).
It's certainly not the case now that there is literally an API that tracks that.