Custom web application
A custom web application is software built specifically for your company. It opens in a browser and matches exactly how you work, instead of bending your business to fit a generic tool. Not a brochure site, not an online store: a business tool that does the work your team does today by hand, in Excel, or across five apps that don't talk to each other.
Almost anything is technically doable. The real question is elsewhere: how much it costs, how long it takes, and how to avoid the 40,000 € quote that delivers an empty shell two years later.
A custom web application is software built specifically for your company, reachable from a browser, that matches how you work instead of forcing its own way on you. Expect 15,000 to over 100,000 € on the traditional market. At 5000.dev, 5,000 € per brick delivered in two weeks, source code included.
Custom is not always the right answer. Let's be clear about that before we talk budget.
You want a brochure site or a blog (Webflow or WordPress does the job for a few hundred euros); you sell standard products online (Shopify exists, don't pay anyone to reinvent it); you just want to test an idea with five customers (a Google Form, a spreadsheet, and three calls validate the need before the first line of code).
You re-enter the same information across several tools, and it gets lost in an email on the way; you pay 400 € a month for a SaaS your team uses as a barely disguised Excel; your process is too specific for any off-the-shelf software; you need to own the code, manage access and roles, take payments, automate follow-ups, handle sensitive data.
An eight-person kitchen fitter running its job sites across twelve Excel tabs doesn't have a website problem. It has a copy-paste problem. That's exactly what a business application solves.
The market will tell you "between 15,000 and 200,000 €", which helps you decide nothing. And that's exactly the problem. On a typical agency quote, a large share of the money does not fund your software. It pays a middle project manager, an overhead structure, a margin, and the back-and-forth of an endless spec document. The part that actually produces code rarely tops a quarter of the quote.
Our stance is different: 5,000 € for a first working brick, deployed live, with the source code that belongs to you. Fixed price. If the scope goes beyond what we can ship cleanly, we cut it into several bricks instead of inflating one invoice nobody controls. For the full ranges, see our page on the cost of developing an application.
Why this price holds today when it was unthinkable three years ago: AI cuts code production time by four, as long as senior developers orchestrate it. A non-developer who codes "by feel" with AI produces technical debt that costs more to fix than to rebuild. We hand the AI productivity back to the client as a fixed price, not as billed hours.
For years, custom was reserved for big budgets: six months of specs, eighteen months of development. Many small businesses defaulted to off-the-shelf software because they couldn't afford anything else. That was the rational choice.
AI broke that math. Senior developers who orchestrate AI well ship in two weeks what used to take two months. Code production cost is cut by roughly four. What was out of reach for a small business yesterday becomes affordable today.
Watch the opposite trap: a non-developer who codes by feel with AI (vibe coding) produces technical debt that breaks the moment a real business rule, a payment, or sensitive data comes into play. AI speeds up senior developers who know how to scope, cut, and ship; it doesn't replace that scoping. That framed productivity is what we hand back to you as a fixed price.
Two weeks per brick. Fifteen working days and the application is live. Those two weeks cover only the development. All the understanding work happens before kickoff: the business, the constraints, the mockups of every screen. The developer never codes in the dark. That preparation is what makes two weeks possible, not a team sprinting at nothing.
Discovery call. We understand your business, your problems, and what you concretely do today.
Technical call. We dig into the constraints, your data, the integrations with your existing tools.
A clear spec page, drawn from the two calls. You read it, you validate it. Go or no go, no disguised commitment.
Mockups of every page of the final application. You picture it, you give feedback before a single line of code is written.
Go, the clock starts. Fifteen days of development, the application is delivered.
Building brick by brick cuts the risk through small concrete deliveries, instead of promising the perfect application in six months and delivering it in two years.
A network of at-home car-care tradespeople (mechanics, body shops, detailers) ran its appointments over the phone and by text, with no overview and no online payment. First brick shipped in two weeks: each professional creates a profile, their rates, and their calendar; the customer searches by service and by area, books a slot, describes the need (model, mileage), and pays online. We didn't build the full marketplace in one shot. We shipped the brick that runs the booking, live, at 5,000 €. Reviews, dispute handling, and subscriptions came in the next bricks.
| No-code (Bubble, Airtable) | Off-the-shelf SaaS | Custom application | |
|---|---|---|---|
| For what | Testing an idea fast | A standard, common need | A specific, lasting process |
| Cost | Low up front | 200 to 600 €/month, forever | 5,000 € per brick, once |
| You own | Nothing, you rent | Nothing, you rent | The code is yours |
| Limit | A fast technical ceiling | You bend your business to the tool | None, it's built for you |
| Right moment | Validate before building | The need fits the standard offer | The standard tool holds you back |
No-code is an excellent starting point to prove an idea has value. The day the prototype becomes a tool your business depends on, you have to move it out of no-code into a real, maintainable application. That's a transition, not a failure.
A document that's dead before it's finished. Nobody reads it in full, it freezes decisions made too early, and it bills months of scoping before any result. One clear spec page is enough to start.
The bigger the scope, the longer, costlier, and riskier the project. A first working brick running in two weeks teaches you more than six months of meetings.
A button is simple to display. What can be complex is the action it triggers. A good technical partner's job is to translate your business idea into the simplest solution that works, not to code everything you imagine.
To choose who you trust with this work, read our guide on picking an application development agency. And for a concrete case, look at custom software.
The code belongs to you, delivered and deployed. You're locked to no one. We handle what comes next only if you want us to.
Every brick ships with three months of warranty. We fix bugs and the adjustments planned in the scope, at no extra cost. That window also lets you measure your real needs before talking about a plan.
If you want us to keep going, the plan starts at €200/month for security and fixing any bug. Depending on the volume and real needs of your project, it scales up to €1,000/month at most for regular improvements. We calibrate it after the three-month guarantee, at the right level. The plan is optional and runs on a one-year commitment, and nothing stops you from leaving with your code.
Our €50/month plan runs on a server we manage for you, with backups, monitoring, and visit statistics. If you'd rather host elsewhere, the code is yours and we deploy you there (500 € for a first deployment off our servers; on our side, the deployment setup is included in the brick).
Your requests go through WhatsApp and a ticket-tracking tool, so you keep control over progress.
If you re-enter data from one tool to another, if you pay for a subscription you bend into a spreadsheet, or if no off-the-shelf software fits your business, you probably need custom. Not a six-figure project: a concrete, bounded first brick, live in two weeks.