# You Should Be Building Your Own Software > You don't need to code to build software that fits your life exactly. And building it makes you better at the thing it's for. *Published: 26 Sep 2026* *Tags: Personal Software, AI* --- In March I built an app to answer one question about our household money. Six months later **it's the most useful software I own**, and nobody else will ever use it. I wanted to know what salary sacrifice would actually do to us, with our salaries and our childcare costs, in Northern Ireland, this tax year. Every calculator I found answered a slightly different question, and none of them let me change one thing and see what it did to everything else. So I built Monies. It models our income, tax, National Insurance, student loans, child benefit, tax-free childcare and pension against the mortgage, then projects it all forward. I can set up a "what if" and compare it side by side with where we are now. That was the first version. Since then it's grown a mortgage page, stamp duty, long-term wealth projections and, this week, a page for selling a house, with valuations, agents' fees and what we'd actually walk away with. No product I could have bought would have grown with me like that. ## The tools have caught up ![A speech bubble becoming an app window](/assets/images/posts/025/tools-caught-up-minimal.png) I think you should be building your own software, shaped around your own life and work. You don't need to learn to program to do it. A couple of years ago that would have been a ridiculous thing to say to anyone who wasn't an engineer. Now, with tools like [Claude Code](https://claude.ai) or [Codex](https://openai.com/codex/), you describe what you want, look at what comes back and say what's wrong with it, over and over until it's right. **Making a tool often costs less than putting up with one that nearly fits.** It's hard to say exactly what to call this, because it's still emerging. Some people say personal software. Others say home-cooked software, after [Robin Sloan's essay](https://www.robinsloan.com/notes/home-cooked-app/) about the app he made for his family, and it overlaps a lot with [local-first software](https://www.inkandswitch.com/local-first/), which is about keeping your data on your own machine. [Maggie Appleton](https://maggieappleton.com/home-cooked-software) was writing about the idea years before the tools could actually do it. ## It fits you exactly ![An app window shaped to fit around a person](/assets/images/posts/025/fits-person.png) Every piece of software you've ever bought was built for the average customer, and I've never met anyone who is one. I'm on the other side of this at [Stora](https://stora.co). A software company is trying to build something that works for as many people in its market as possible, so it looks for the broadest needs and meets those. Every customer has their own needs on top, and most of them never get met. Plenty of them are good ideas. There's just always something more important to do, whether that's what grows the business or what keeps most customers happy. That's how software businesses have to work. Any one of them has hundreds of good ideas that will never get done, for no reason other than that something else mattered more. So the feedback you leave goes on a list you'll never see, and nine times out of ten nothing happens. With your own software, the only things standing between you and what you need are spotting it and putting the effort in. Most of the time it's fixed before your coffee's gone cold. The part I love most is that **it changes when you do**, often the same afternoon. Monies didn't have a selling page in March because I didn't need one in March. Bought software can't do that. It's also why most of mine will never be products. Every change I make to suit how I work takes it a step further from anything a stranger could pick up, and I'm fine with that. ## It makes you better To build a tool for your own problem you have to understand the problem properly, often for the first time. You can't describe what you want until you know what you want, and working that out is the useful bit. I understand our finances better now than any adviser ever explained them to me. Building Monies made it easier to ask questions, because I knew I had something that would answer them in a way I could understand. And when I couldn't understand the answer, I kept working on it until I could. It's the same thing I've been writing about at work. [The people leaning into AI are pulling away](/writing/how-to-stay-indispensable-when-ai-changes-everything/) from the people who aren't. Building your own software is what leaning in looks like outside your job. ## "But I can't code" ![A person and an app exchanging speech bubbles](/assets/images/posts/025/cant-code-minimal.png) Plenty of people doing this can't either. I'm a designer by trade. What made Monies possible was knowing exactly what annoyed me about every calculator I'd tried, and being stubborn enough to keep describing it until the thing on screen matched the thing in my head. The other half was experimenting. I'd spent a lot of time pushing these tools just to see what they could do, so I knew something like Monies was within reach. Most people haven't played with them at that level yet, so they don't know what's possible. If you work in product or design, you already do the first half for a living. You spot what's wrong with something and you can explain why. That turns out to be the hard part. **When building costs almost nothing, knowing what you want is most of the work**, and in my experience people who can describe what good looks like are harder to find than people who can build it. The process is less technical than you'd think: - Describe the problem and the thing you wish existed. - Whatever comes back will likely be wrong in some way. Say how. - Build it, then try using it and see what you think. - Whatever you find yourself missing is your next ask. You'll pick up everything else as you go, the same way you picked up every other tool you use. ## Start local, ship when it's earned it ![Two apps staying on a computer while one is shared beyond it](/assets/images/posts/025/start-local-minimal.png) The objection I hear most is maintenance. Who's going to keep all this running? Most of what people worry about, like hosting, logins, security and support, only matters once you're shipping software to other people. Keep it on your own machine and most of it goes away. Monies lives on my laptop, so there's no server to break and no account to hack. When a tool earns it, say you want it on your phone or your family wants to use it, take those problems on for that one tool and leave the rest alone. ## My software graveyard ![Three app-shaped gravestones with a small orange sprout beside them](/assets/images/posts/025/app-graveyard-minimal.png) I should admit that plenty of what I build doesn't last. In March I kept losing track of my side projects, so I made Onesie, an app to keep track of them and jump between them. I don't use it any more. Then I had so many projects on the go that I couldn't remember which servers I had running, and I hate having to start them up from a pile of terminal tabs. So I built a tool that just showed me what was running, and that's gone too. There's also a long tail of things I started and never finished. I don't mind, and I think it's one of the best things about building this way. Each of those cost me a few evenings. When something doesn't work I learn what I actually needed and have another go, and the tool I use every day now only exists because the first two taught me what it should be. When software took months to build, throwing it away hurt. You'd keep patching something that wasn't working because of everything you'd already put into it. That sunk cost mostly disappears when a replacement takes an evening, and **being able to try something, bin it and start again that quickly is a bit of a superpower**. ## Buy or vibe None of this means you should build everything. I still pay for plenty of software. So the question I ask now is simple: buy or vibe? I buy anything where money, security or other people depend on it, so my password manager, my bank and my backups aren't going anywhere. Same for anything that's only useful because everyone else is on it, like messaging. The biggest factor, though, is complexity. **When I build something I'm paying with my time instead of money**, so the real question is how long it's going to take. Monies was worth the evenings I've put into it. Something ridiculously complicated never would be. Once you're honest about how much is really going on in the thing you'd be replacing, it's usually obvious which side it falls on. I sell software for a living, so I've thought about this one a lot. I'm not about to build my own Stora. The screens would be easy enough. What took years was watching how customers actually use it, getting it wrong and going again, and you can't get that from a prompt. I vibe it when it's just for me and my way of doing things is a bit weird, so nothing I can buy quite fits. Especially if I know it's going to keep changing. And vibing doesn't have to mean starting from nothing. Plenty of things already have a good open-source version, so you can start from that and get Claude or Codex to bend it to fit. It's still vibing, just with a head start. That's what a lot of people seem to be doing with photo editors and booking tools. ![Banking, calendar and health services connected to one personal app](/assets/images/posts/025/buy-or-vibe-minimal.png) Some of the most interesting stuff sits in the middle. **Buy the data, vibe the interface.** Keep paying for the fitness tracker, and build the layer on top that pulls it together the way you want it. That's what I'm doing with Longa, which pulls in my WHOOP and smart scale data so I can look at it my way. It's one pattern of a few, though. Monies runs on numbers I type in myself, and some of my tools just work on what's already on my Mac. I'll write more soon about how I decide. ## The usual objections ![A person responding to three question marks, with one highlighted in orange](/assets/images/posts/025/usual-objections-minimal.png) **"It'll be slop."** It only has to be good for one person. You're the whole market, so the bar is whether it works for you. **"You've just swapped your subscriptions for one big one."** Partly true. I've traded a pile of small subscriptions for a dependency on one AI tool, and that company has more power over me than any of the others did. It's better today, but I'm honestly not sure it's better forever. **"You won't understand what you've built."** Some of what I've built works and I couldn't tell you why. When it's just for me I don't really care. If it works, it works. If I wanted other people to use it, that's when I'd start to care. **"Normal people won't do this."** Plenty already do, they just do it in spreadsheets. The household budget, the wedding planner, the five-a-side fees tracker. I'd argue building one of those is harder than building a personal tool with AI. Formulas and lookups take real learning, but everyone already knows how to have a chat. Once you're past the initial setup and stop worrying about the technical side, there isn't much more to it than describing what you want. **"SaaS isn't dead."** Agreed. Buy the platform and vibe the bit on top. ## Where this goes More people are doing this every month. Most of them aren't engineers and most of them don't call it anything. They just build the thing they need. Once you've built one, it stays in your head. You start noticing every bit of software that nearly fits, and it snowballs from there. It did for me, anyway. As more people open that can of worms, I expect a lot more of them will look at the next subscription and pick vibe over buy. [Retool asked 817 of its customers](https://retool.com/blog/ai-build-vs-buy-report-2026) earlier this year, and 35% had already replaced at least one piece of software they paid for with something they'd built. 78% expected to build more. Retool sells the tools for doing exactly that, so take it with a pinch of salt, but it matches what I'm seeing. A thread on r/ClaudeAI this week asked people [what paid software they'd replaced](https://www.reddit.com/r/ClaudeAI/comments/1wr61sr/what_paid_software_or_subscription_did_you_replace/), and it got over a hundred replies in a day. QuickBooks, Calendly, Evernote, Microsoft Project, a couple of CRMs, and plenty of weight trackers and budget apps. The top answer summed it up: they'd been paying for an app every month and only using three of its features. The tools to make this normal are still catching up, and I'm building some of them. I've got more than a dozen of these little apps on my Mac now, and keeping them straight got messy enough that I built something for that too. It's called [Platter](https://plattermac.com), and it keeps them all in one place. You don't need any of that to start, though. Think about the last time you went looking for something to solve a problem and couldn't find it, or the software you put up with every week because it nearly fits. That's your first one. I've written more about how AI is changing the work itself in [someone is going to automate your job](/writing/someone-is-going-to-automate-your-job/) and [the death of the pixel pusher](/writing/the-death-of-the-pixel-pusher/).