I build custom web applications: systems that run a company's daily work and products your clients pay to access. Design, code, payments, server, and maintenance stay with one person, from the first conversation through years of growth.
Types
The first conversation starts with settling who will use the application. Everything downstream depends on it: the screen layout, the way people sign in, and whether payments are needed at all.
Work that is currently scattered across a spreadsheet, email, and a notebook.
No more asking who has the case and digging for files in email.
A service your clients pay for and use on their own.
You sell subscription access, and revenue grows with the number of clients.
Uses
Below are the areas I get asked about most often. An application usually combines several of them, because inside a company everything is connected anyway.
Incoming requests, assignment to people, statuses, deadlines, and change history. All of it visible to the whole team.
A contact database, offers, contracts, and follow-up reminders. Data goes in once and is available everywhere.
A calendar with availability, client sign-ups, confirmations, and reminders sent automatically.
Stock levels, releases, equipment assigned to an employee, inspections, and service dates.
Contracts and invoices generated from the data in the system, an approval flow, and a searchable archive.
The numbers you actually look at, refreshed on their own, straight from the system.
Timing
If at least two of these points sound familiar, a conversation usually makes sense. During it I say plainly whether I see a cheaper route to the same goal.
Scope
Projects
Everything below has real users, payments, and its own backend. I maintain these applications personally, so I see how they behave after years in service. How one of them is built and what it costs to run is covered in the post how I built Matury Online.
An education platform with payments
Student accounts, eleven subjects, over 16,000 questions, a full exam mode, and essay grading based on national exam-board criteria. Listening recordings for foreign languages are generated during the exercise.
A product sold by subscription
Balance-based billing, a job queue, and an automatic refund when a job fails. The same backend serves the panel, the mobile app, a public API, and the Zapier and n8n integrations.
A tool with add-ins for other programs
The application fetches documents, reads the page numbers printed in them, and builds citations from that. The same user works with it in the browser, in Word, and in Google Docs, on a single account.
Technology
The same set powers my education platform, a content generator, and an online store. The logic changes, the foundation stays — so each next launch costs a fraction of the first, and you never pay for the basics to be reinvented.
Node with TypeScript on an AWS server. Restarts with no downtime, so updates ship during working hours.
PostgreSQL, a database proven in financial systems. Daily backups, with regular restore tests.
React and Astro. The application opens fast and works the same on a desktop and on a phone.
Servers, files, and email in the AWS cloud, in data centres within the European Union.
Price
The first working version starts at 15,000 zł net. A larger system with several roles, payments, and connections to other programs usually lands between 30,000 and 80,000 zł. I quote in stages, so you pay for the next step once the previous one works.
from 15,000 złnet, first version
What drives the price:
Maintenance comes on top — server, backups, monitoring, and updates — from 600 zł per month, depending on load.
Calculator
Tick what it should include. The amount recalculates as you go and shows what each item adds.
Process
You describe how the work runs today and what should change. After an hour it is usually clear where to start.
Features split into what must be there at launch and what can wait. This is the cheapest moment for decisions.
A price for the first working version, a deadline, and a list of what is included. One amount per stage.
I build what is genuinely needed for the work and put it under an address you can access from day one.
The team starts using it and I fix whatever gets in the way. This stage changes the most.
Further features added when they are needed, in an order driven by how you actually use the system.
After launch
A session on your own data, run separately for employees and for the person in charge. The recording stays with you.
A code repository, server access, and documentation. Everything registered to your company.
For the first month after launch I fix and explain as much as needed, within the implementation price.
Server, backups, monitoring, and updates from 600 zł per month. New features quoted separately.
Questions
The first working version starts at 15,000 zł net. A larger system with several roles, payments, and connections to other programs usually lands between 30,000 and 80,000 zł. I quote after scoping, as a single amount per stage.
I work alone, so the price carries no project manager, salesperson, or office. The same person talks to you, designs, writes the code, and runs the server, which means you never pay for tasks being handed around or context being explained again.
A first version you can genuinely work with takes four to ten weeks. Growth then proceeds in stages of a few weeks each. We start with what the work requires; the rest arrives in later versions.
When your company's process differs from what off-the-shelf programs handle, when you pay per-user licences with a growing team, or when you want to sell access to your own tool. On the first call I say plainly which option will cost you the least.
You do, together with the copyright. You get the repository and full server access, so you can hand development to someone else, or to your own team, at any moment.
On AWS cloud servers, in data centres within the European Union, in line with GDPR. Backups run daily, and every so often I check that a full restore actually works.
In most cases, yes. I have connected systems to Allegro, BaseLinker, warehouse and invoicing programs, and Google Sheets. If a program offers an API or file export, it can be done. I confirm this at the quoting stage.
The application is designed for features to be added. I quote new modules separately and roll them out in stages, with no interruption to work. Several of my own products have grown this way for years.
Yes. The mobile app uses the same backend as the browser version, so data and logic are shared. That is how Matury Online works, where the same user moves from desktop to phone with progress intact.
Related services
Projects rarely stop at one thing — here is the rest of what I do, each with its starting price.
Order
A few sentences about what you do by hand, or about the product you want to build, are enough. I'll reply with a proposed scope, a quote for the first version, and a schedule — usually the same day.