A tool for monitoring website availability and response times. Every minute it checks whether a site is up, measures the response time and sends an alert immediately when it goes down.
Available for smaller projects
Ing. Václav Kovalčík
Web and mobile app developer in Prague
For more than 25 years I have been putting my experience to work for clients and helping them grow their profits over the long term. I focus on modern web applications in React and PHP (Nette/Symfony). I have recently started building mobile apps in Swift as well.
25+
years of experience
120+
projects
B2B
specialist
Experience
since 2002
Down
About me
I keep learning new technologies and following new methods and trends in IT. I build websites, e-shops, sophisticated admin panels and bots that collect the data you need, as well as mobile apps for iPhone, iPad and macOS.
I also work in development teams, where I help clients improve their web applications.
What I do
I build modern applications
Web applications
Front-end development in React and TypeScript. Components, SPAs, API integration, UX/UI.
Backend & API
Design and development of robust backends in PHP (Symfony, Nette), REST APIs, databases, messaging and performance optimisation.
Mobile development (iOS)
iPhone, iPad and macOS apps in Swift and SwiftUI – from design and API integration to App Store release. More at ios-developer.eu
Services
Automation and data processing
Price lists, enquiries, invoices and catalogues processed automatically and connected to your system. No more manual retyping. More about automation
PHP project takeover
Has your developer or agency left? I take over applications in Nette, Symfony or legacy PHP, stabilise them and keep developing them. How a takeover works
PHP application audit
Code, security, performance, database and the path to PHP 8.4/8.5. A written report with priorities and effort estimates. What the audit covers
Custom application development
B2B systems, admin panels, booking, invoicing and configurators in Nette, Symfony and React, integrated with your existing systems. How custom development works
Stack
What I code in
PHP · TypeScript · React · React Native · Swift · SwiftUI · REST API · MySQL · PostgreSQL · Oracle · Mongo · Redis · RabbitMQ · Docker · GitLab CI/CD · PHPUnit · Selenium · Mockery · Codeception · JMeter · Elasticsearch · Kibana · Bash · Composer · OpenStack · Scrum · Kanban · SOLID · DRY · KISS · OOP · and more…
Clients who have valued my work
Portfolio
Selected case studies
ios-developer.eu
2025 – 2026A project focused on building native iPhone and iPad apps in Swift and SwiftUI – from architecture design through API integration to App Store release.
vyjadreni.net
2016 – 2026A large web application for electricity network statements. It handles invoices, payment reminders, user roles, bank payment matching, SMS and other notifications. Case study →
konfigurator.agrio.cz
2015 – 2026A configurator for agricultural machinery manufacturing with thousands of calculations. I learned the logic behind the machine designs and then trained the sales staff. Multiple languages, price list versioning. Offline and online versions. Case study →
Borra
2019 – 2026A web application for preparing quotations and tracking order status in production. Technologies: Nette, CI/CD in GitLab, Doctrine, migrations, automated code quality checks.
Nerezove-zabradli-palamar.cz
2013The brief was a 180-page PDF with tables and photos. I bulk-processed the file, extracted 2,000 products and then built the e-shop.
online.ulzibat.cz
2015 – 2019A booking system for consultations and surgeries with up to 9 user roles. When a slot frees up, it is automatically filled from the waiting list. Data export to Excel.
Realne-simulatory.cz
2012 – 2015A large booking and invoicing system where you choose experiences. Custom features for admins, clients, experience agencies, pilots and flight attendants.
You will find more references at Ananas.cz
Articles
Technical articles
Upgrading PHP 7 to 8.4/8.5: a practical guide for business applications
An application on PHP 7.4 or 8.0 no longer receives security fixes, and the longer you put off the upgrade, the more it costs. Moving to PHP 8.4 or 8.5 can be done gradually and without downtime: an audit, tests, automated changes with Rector, static analysis, updating libraries and the framework, and deployment in small steps. Read article
When your PHP developer or agency leaves: what to do now and what next
When a developer or agency leaves, secure access first: you must be in control of the code, server, database, domain, hosting and all passwords and keys. Then ask for a proper handover, have a new developer assess the code, and decide on a rewrite only once you have the audit results in hand. Read article
Pricing
Development pricing
For an unambiguous brief, I prepare a no-obligation quote as a price ceiling that I will not exceed. I can also help you put the brief together, carry out a detailed project analysis and flag potential risks.
Standard hourly rate (billed per minute)
2,500 CZK / h
Service agreement: 20 h/month prepaid, minimum 12 months
2,250 CZK / h
Large projects of 300+ h (min. 84 h/month), billed in 1-hour increments
from 1,800 CZK / h
Long-term projects: 12+ months, 8 h billed every day
10,000 CZK / MD
Training and talks
3,000 CZK / h
Express surcharge approved by the client (work starts within 2–12 hours)
+ 20%
Prices valid from 1 June 2026 · Prices exclude 21% VAT · New clients receive pro forma invoices · MD (man-day) = 8 hours of work
Pricing for specific services: Automation and data processing · PHP project takeover · PHP application audit · Custom application development
FAQ
Frequently asked questions
How much does web application development cost?
The price depends on the scope of the project. My standard hourly rate is 2,500 CZK/h excl. VAT. For projects of 300 hours or more, the rate is lower (from 1,800 CZK/h). For a clearly defined brief, I prepare a no-obligation quote as a price ceiling that I will not exceed.
How long does a project take?
I handle smaller changes and fixes within days. An MVP web application usually takes 4–8 weeks. Large B2B applications run as long-term engagements of 6 months or more. Once I receive the brief, I provide a specific time estimate.
Do you work for an hourly rate or a fixed price?
I offer both. An hourly rate suits ongoing changes and projects with an unclear brief. I prefer a fixed price (price ceiling) for clearly defined projects. I bill per minute, not per hour.
What technologies do you work with?
Backend: PHP (Nette, Symfony), REST API, MySQL, PostgreSQL, Redis, RabbitMQ, Docker, GitLab CI/CD. Frontend: React, TypeScript. Mobile development: Swift, SwiftUI (native iOS apps). I have 25 years of experience developing business applications.
Do you only work for clients in Prague?
No. I work remotely for clients across the EU. In-person meetings in Prague are possible, but most of the work happens online (email, video calls, GitLab). I communicate in Czech, English and German.
Will you take over a project from another developer?
Yes. I often take over legacy projects from other developers. I first carry out a code audit (typically 4–8 hours), propose a migration or refactoring approach, and only then start working on the project. I specialise in rescuing Nette and Symfony applications.
Do you use AI in development?
Yes, as a tool – for the routine parts of development, generating tests and processing data. It makes me faster, which is reflected in the price of the result, not in the number of hours billed. Responsibility for the final code is always mine.
Contact
Contact and enquiries
I reply within 1 working day.
Ing. Václav Kovalčík
Registered office
Evropská 692/14, Prague 6 – Dejvice
Phone
+420 737 981 440
Email
php@vaclav-kovalcik.cz
Company ID (IČ)
71643605 · VAT registered
Area served
EU countries
Sole trader (self-employed individual)
Registered in the Trade Register since 15 May 2002
Trade licence no.: 310028-2875165-00
Registering authority: Municipal Office of Prague 17