Episode 21 — The doctor asked for one thing. I built something else

Tell me a story you've never told publicly.

About the time a doctor asked you for a feature and you didn't build it.

That sounds like an accusation.

It's a bit of one.

Hello, I'm Tomasz Szuster.

I built the mojApteczka app.

And this story is about how, sometimes,

the most honest answer to a specialist's request

is to build something other than what they asked for.

And then explain why.

Start at the beginning, then.

What did they say?

The doctor suggested something simple,

that the owner of the medicine cabinet

should be able to flag a medicine they're allergic to.

One field, you tick it, and that's that.

And that sounds sensible.

It sounds sensible,

and that's exactly how I'd have built it if I hadn't stopped for a day.

What happened in that day?

I asked myself what happens when a different box turns up in the cabinet.

Meaning?

You flag the allergy on one particular pack.

A month later, you buy a medicine from a different company.

Different name, different box.

Inside, the same substance.

And the app says nothing.

Says nothing.

Because the flag was sitting on that box,

not on the substance.

And that's precisely the case where the warning was needed most.

So the feature would exist.

It'd look good on a list of features.

And it'd stay quiet at exactly the moment it ought to speak up.

That's worse than not having it at all,

because it gives you a false sense that somebody's keeping an eye out.

So what did you build instead?

I moved the allergy off the pack and onto the active substance.

And I added a second dimension that wasn't in the original request at all.

The person.

The person?

Because a medicine cabinet at home doesn't belong to one person.

An allergy belongs to a particular human being.

You, me, a child, grandma.

The warning has to know who it's about.

Otherwise it's just noise.

That seems obvious when you put it like that.

It seems obvious afterwards.

It wasn't in the request,

because the doctor was thinking about the patient sitting across the desk from them.

I'm dealing with a drawer that five people use.

By the way, everything we're talking about here really is a feature in the mojApteczka app.

This isn't an advert, just context to be clear.

Right.

But now I want to hear the other side,

because you sound as though you've solved it.

I haven't solved the whole problem.

And that's actually the more important half of this episode.

Go on.

There are three things this feature doesn't do,

and all three are written down in the design documentation

as deliberate limitations of the current version.

As boundaries, you have to say out loud.

The first?

There's no cross-reactivity.

In plain terms,

if you enter an allergy to one substance,

the app will not automatically warn you about another related one,

unless you enter that one separately as well.

Hang on.

That's fairly serious.

It is serious.

Which is why I'm saying it on a podcast,

and not only in the documentation.

Drug classes are clinical knowledge,

and I'm not going to build that on my own out of a database of names.

This is exactly the point where a conversation with the pharmacist

has no substitute.

The second thing?

The substance matching is

heuristic,

which means that,

with an unusual spelling,

the warning might not appear at all,

and sometimes it might appear when it needn't.

So it can both miss things

and give you a fright.

Both.

And again,

I'd rather say so

than pretend to a precision I haven't got.

And the third?

The third is the most contentious.

The app warns,

but it never blocks.

It doesn't block.

So I can see the warning

and still hand that medicine out?

You can.

It's deliberately built that way.

Explain that,

because at first glance it sounds irresponsible.

Because I don't know what situation you're in.

Maybe the doctor decided that deliberately.

Maybe the entry is out of date.

Maybe it was a slip when it was typed in.

An app that blocks

is making a medical decision on a person's behalf,

and that's not something it's allowed to do.

So blocking would look safer,

but it'd be crossing a line.

Exactly.

A warning says,

check this.

A block says,

you mustn't.

Only one of those is mine to say.

You said those are documented limitations,

but was there a bug that actually happened?

There was,

and it's an uncomfortable one.

With a feature that works per person,

the most dangerous class of bug

is one person's data leaking onto another.

Meaning,

my allergy shows up against Leon's medicine.

Exactly that.

And it isn't theoretical.

It's the class of mistake

that had to be closed off with tests of its own.

Because that kind of bug is sly.

The app still works.

It still shows you something.

It just attaches it to the wrong person.

And nobody notices,

because the warning looks perfectly normal.

Completely normal.

Which is why,

with family features,

what interests me least

is whether something displays.

What interests me

is whether it displays

to the right person.

Now the question

we probably should have started with.

How often do medicine mix-ups

happen in Polish homes?

I don't know.

What do you mean,

you don't know?

I don't know of a reliable Polish figure.

And I want to be precise here

because these are two different things.

Which two?

The first is an adverse reaction to a medicine.

The medicine did somebody harm.

There's an official route for that.

A patient,

a carer,

or a pharmacist can report it.

That works.

And it's good that it works.

And the second?

The second is a plain mix-up.

Taking the wrong medicine.

A double dose,

because two people both gave it.

Giving a child

something meant for adults.

Here the medicine did exactly

what it was supposed to.

It just went to the wrong place.

And you couldn't find

that collected anywhere?

I haven't found a public,

systematic picture

of what goes on

at the drawer at home.

I could be wrong,

and I'd be glad

if somebody showed me

that such a picture exists.

So you haven't got a number?

I haven't.

And I could do the thing

half this industry does,

take a statistic

from another country,

multiply it by the population,

and present it as a Polish one.

It'd look very convincing

on a slide.

But?

But it'd be made up.

A different health system,

a different way of counting,

different habits.

It doesn't scale by head count.

So you're building

a safety feature,

and you don't know

how much of the problem

you're solving.

I don't.

And honestly,

that's the most frustrating thing

about this job.

I don't know how many times

a warning like that

has genuinely helped somebody,

because the help

consists of something

not happening.

And I can't see that

measured anywhere.

So,

what do you do about it?

You can't set up

a register on your own.

I can't,

and I shouldn't.

But I can say out loud

that the number

is missing.

Because as long as there's

no public,

systematic measurement,

it's easy to treat this

as a problem nobody can see.

And things nobody can see

rarely get programs

and money.

And that's the ask.

That's the whole ask.

Not,

buy my app.

Just,

let's count it.

Anyone.

If only so it turns out

the problem is smaller

than I think.

Would you be alright

with that result?

I'd be alright

with any result

that's true.

I'm not attached

to the problem being big.

I'm attached

to it being known.

I'll add mine,

in ordinary human terms.

In our house,

the medicine cabinet

isn't one shelf

belonging to one person.

Leon's nine,

Basha's five,

and those are

completely different medicines.

And then there's my mum,

who sometimes stays over.

And that's the drawer

I was talking about.

Not the patient,

but four people

and one box

for the lot.

Which is why,

if I've got any doubt at all,

I take the pack

and go to the chemists.

And that's the right answer.

The app's job

is to remind you

there's something

worth asking about.

The answer

belongs to the pharmacist.

If you'd like to give it a go,

you'll find the link

to the mojApteczka app

in the episode description.

The app is free

and your medicine cabinet

is there offline too.

And if you enjoyed this episode,

share it with someone

who sorts out the medicines

for the whole family.

One more thing

before we go.

This podcast

is made with the help

of artificial intelligence.

I wrote the dialogue myself,

but the voices you're hearing

aren't ours.

They're AI-generated,

synthetic voices.

We're telling you this

straight out

because we think

it should be the standard

for any podcast

made this way.

Full details

are in the show notes

and in every episode description.

Until next time.

Until next time.