Typical duration: 4–10 weeks
Budget band: EUR 3,000+

Web applications

What separates a web application from a brochure site is the data inside it: who can reach what starts to matter, and mistakes have to be reversible.

What is built

The data model first, screens second

What is stored and what is derived gets separated at the outset. Screens drawn before that separation end up, six months later, showing the same fact two different ways in two places. Once the model is written down the interface is built on top of it, not the other way round.

Identity and permission are two questions

Who you are and what you can reach are solved separately. Roles are counted, the data each role must not see is written down explicitly, and the rule is enforced on the server rather than in the interface. Hiding a button does not count as an access check.

Everything submitted is validated twice

Data from a form is checked against a schema once in the browser and again on the server. Without the second, the first is only a convenience: no obstacle at all to someone who intends to skip it.

Measurement and error tracking ship with it

Once live, which operations run how often and where they fail is visible. Reporting a fault does not depend on a user describing it; the record is already there, and which step broke can be read off it.

How the process works

01The flows get written down
Before a screen is drawn, who arrives to do what is written in sentences. The questions this raises are the cheapest questions available: that a role is redundant, or that two flows are really one, becomes visible before any code exists.
02Data model and API contract
What the interface will ask the server for, and what it gets back, is settled first. Once the contract is clear both sides can move in parallel, and integration stops being a surprise met at the end.
03Delivered screen by screen
Nothing waits for the whole application to be finished. A working slice can be seen early, talked about, and steered while steering is still cheap. The misunderstanding noticed last is the expensive one.
04Deployment and handover
Environment variables, backups and access accounts are set up, and releasing is reduced to a repeatable command. What information is needed to run the system is handed over in writing.

What sets the price

What moves the price is not the number of screens but the number of distinct user roles and how many outside systems connect; a single-role internal tool sits at the bottom of the band and a multi-role dashboard pulling live data sits a long way above it.

how many distinct user roles there are
how many outside systems connect: payment, email, ERP, calendar
whether real-time updates are required
how deep the reporting and export requirements go
whether data has to be migrated from an existing system

Common questions

Should this be a mobile app or a web application?

The question it turns on is whether the phone's own capabilities are needed. If notifications, camera, location or offline use are required, a mobile app can be justified. If not, a web application runs on every device from one codebase, waits for no store review, and ships an update the moment it is ready.

Where does the data live?

The hosting region is chosen before work starts, and it is usually a requirement rather than a preference: for an application handling personal data, which country the data sits in is decisive under GDPR and KVKK. Because the accounts are opened in your name, access to the data is yours from the beginning.

What happens if the number of users grows?

The setup runs on infrastructure that grows with the user count, so a small plan is enough at the start and growth does not force a rewrite. What breaks first under load is usually decided in the data model, which is why that step is not rushed.

Can it talk to our existing system?

If the other system has an API, yes. If it does not, intermediate routes such as file transfer or scheduled synchronisation are set up instead. Which of those is possible is answered after its documentation has been read, not in the first conversation.