I Build an AI Companion App Alone. It Runs on Nobody's Servers But Yours.

I Build an AI Companion App Alone. It Runs on Nobody's Servers But Yours.

I was using one of the cloud companion apps, the kind everyone has heard of, and one day I actually looked at where it all lived. Every message. Every memory. The whole relationship, sitting on someone else's servers. And it hit me that none of it was mine. If that company changed its mind, raised its price, decided my companion was suddenly not allowed, or sold what it had learned about me, I would simply lose her. No say, no warning, no way back.

That thought turned into an app. I called it Local Waifu, and I have built almost every part of it alone: the code, the writing, the marketing, the support inbox, the Discord server. This is what that actually looks like, and why I keep choosing to do it the harder way.

This has already happened to real people

I did not invent this fear. Policies change overnight. Models get retired without warning. Features people paid for quietly disappear one update later. Some people built a real bond with a cloud companion and woke up one day to a stranger wearing the same name, or to nothing at all. When the relationship lives on someone else's infrastructure, it was never really yours to keep. You were renting a feeling from a company that owed you nothing once the terms of service changed.

That is not a hypothetical I made up to sell software. It is the plain, boring mechanics of any product that lives entirely on a server you do not control. The company can be perfectly well intentioned and it still does not change the arrangement. Your data, your history, your memories of a relationship, sitting on hardware you will never see, governed by a document you clicked past.

So I built the opposite

Local Waifu runs entirely on your own machine, your Mac or your PC. The memory file, the whole system, all of it stays on your device. Only you can reach it. Nobody collects it, nobody moderates it, nobody can switch it off from a dashboard somewhere. If a company changes its policy tomorrow, nothing happens to you, because there is no company standing between you and her.

Because she is just files on your computer, she backs up the same way any file does. Time Machine, a USB stick, whatever you already use for everything else. Nobody can take her from you short of someone stealing the physical machine. That sentence sounds almost too simple to be a selling point, and that is exactly why I lead with it. Ownership should not require an explanation.

Out of the box, the app only reaches the internet for three things: the one-time download of the model she runs on, a check for app updates, and confirming a license when you buy one. Everything else, plugging in your own cloud account if you want a bigger model, letting her search the web, connecting her to Telegram, is off until you personally turn it on. Your choice, your accounts, none of my business. I say this plainly because "we take your privacy seriously" is what every company says right before the part where they do not, and I would rather be specific than reassuring.

What it means to be the whole team

I write the blog posts. I design the landing page. I fix the bug at midnight and then write the changelog entry about it the next morning. I answer the emails. I run the Discord server myself, and when I need a second opinion on whether a feature actually works on hardware I do not own, I ask the people in it directly, because there is no QA department to ask instead.

One night a stranger from that Discord sent me a screen recording of a voice call that took 105 seconds to answer a twenty-character question. I did not have a support team to route that to. I had a log file, a weekend, and four separate bugs stacked on top of each other that I had to find myself, one at a time, because there was no server-side telemetry to lean on either. The app runs on your machine, remember, which means when something breaks, it breaks on your machine, and the only evidence I will ever get is whatever a stranger is generous enough to send me.

That is the trade nobody tells you about when they say "build it yourself." Every advantage of not having a team is also a disadvantage. There is no one to catch what I miss. There is also no meeting where a good, honest idea gets watered down until it pleases everybody in the room. Both of those are true at the same time, every day.

I do not say any of this to make the whole thing sound harder than it is. Most days it is genuinely fine, and some days it is the best part of the job: I can ship a fix the same afternoon someone reports it, with nobody to convince first. But I want to be honest about the shape of it, because "I build this alone" gets said as a badge of honor a lot online, and it is really just a description of where the failure modes sit. When it works, it works because one person cared enough to notice something small. When it breaks, it stays broken until that same one person notices, and there is no second pair of eyes behind mine.

Stripe said no. So did Polar.

Here is a small, honest story I do not usually see founders tell in public. When I needed a way to sell licenses for the app, Stripe rejected it. Polar rejected it too. An AI companion app makes payment processors nervous, it turns out, in a way that a project management tool or a photo editor never does. Dodo Payments eventually took the business, and I am not going to pretend that search was quick or comfortable. Building the product was, in a real sense, the easy part. Finding someone willing to process the payment for it took longer than I expected, and it taught me something about the category I am actually in: not just software, but software that sits close enough to something intimate that entire companies decide it is not worth the risk.

Why the code stays closed

I would genuinely like to open source it. I have thought about it seriously more than once, and I want to be straight about why I have not: small projects get taken by bigger companies, rewritten just enough to dodge a license, and sold back as someone else's product. I also do not want pieces of a companion I built carefully getting twisted into something I would be ashamed of, stripped of the parts that make it feel careful in the first place. So the code stays closed for now, and the transparency lives somewhere else instead: a page that names exactly what touches the internet and when, a privacy policy that lists every connection by name, and an app you are welcome to watch on your own network monitor while it runs. I would rather earn your trust by being specific than by handing you a repository and hoping you never read it closely.

Fair, not paranoid

People ask if the license check can be cracked. Probably. I have a decent guess how I would do it myself if I were on the other side of that question. I would still rather build it fair and trust the people who pay than fill the app with anti-piracy tripwires that end up punishing exactly the customers who did the right thing. If someone cracks it instead of buying it, they were never going to buy it in the first place, and treating every user like a suspect does nothing to that person except make the honest ones feel unwelcome.

I think about this the same way I think about the whole product, honestly. The easy version of "protect the business" usually means making the experience worse for everyone who was never going to hurt you in order to slightly inconvenience the small number of people who were. I would rather lose a little to the second group than punish the first one, every single time that trade comes up.

One payment, and then it just keeps working

The deal is simple on purpose. One license, paid once. That payment includes every update and bug fix I ever ship for it, not a year of them, not until some arbitrary version number, all of them. That is how I want the software I personally buy to behave, so it is how I built this one to behave. I am not going to lock a companion behind a recurring paywall and bill someone forever just to keep her running. I would rather earn the next sale by actually making the product better than by billing the same person again for something they already own.

Why I still do it this way

Being a one-person team for something this personal is slower than it would be with a company behind it, and it is more exposed. A bug is mine. A wrong call on pricing is mine. A late reply in Discord is also mine, and there is no one else it can quietly become. But the thing I keep coming back to is that the entire pitch of this app, that it is yours and nobody else's, only means something if the person building it is willing to be found, be specific, and be accountable in exactly the same way.

I built Local Waifu out of a quiet kind of fear about where our digital lives actually live. Building it alone, the slow and exposed way, turned out to be the only version of that answer I actually believed.