Taking on new projects and B2B collaboration
Custom applications and systems built to evolve.
I design and build web and mobile applications, modernise legacy systems and connect them with ERP, CRM, payments and third-party services. From the first idea to running it on the server.
- Full-stack applications
- Modernising legacy systems
- API and ERP integrations
- Maintenance and servers
Services
How I can help
I cover the whole software lifecycle: from analysis and new applications, through modernisation and integrations, to maintenance, security and consulting.
Custom and full-stack applications
New web and mobile applications from analysis to launch: business systems, dashboards, platforms and online shops.
- Full-stack web applications: backend, API and a modern interface
- Tailor-made systems: orders, customers, billing and documents
- Mobile apps (Flutter) connected to your own API
- Shops and sites on WordPress/WooCommerce and PrestaShop, including custom plugins
Modernisation and tackling technical debt
An old system does not mean starting from scratch. I refresh and rebuild existing applications in stages, without stopping the business.
- Audit of the code and architecture of an old application, plus a repair plan
- Rebuilding and updating applications to current technologies
- Code clean-up, tests, PHP and library upgrades
- Step-by-step migration of modules instead of one risky switch-over
API, ERP and payment integrations
I connect systems that exchange data by hand today: shops, accounting, ERP, CRM, banks and payment providers.
- Integrations with ERP and CRM systems
- Invoicing and accounting (e.g. Fakturownia), payment gateways, SMS and e-mail notifications
- Import and reconciliation of bank and external file data
- Custom APIs, webhooks and background data synchronisation
Maintenance, servers and migrations
I keep websites and applications fast and secure, from server setup to day-to-day support.
- Installing and configuring VPS servers, deployments from a repository (CI/CD)
- Moving websites and shops between hosts without downtime
- Fixing outages, bugs, and slow or infected websites
- Backups, updates and database optimisation
Application security
Security reviews and penetration tests of web applications and APIs. Scope is agreed case by case.
- Security review of code and architecture
- Penetration testing of web applications and APIs
- Secure sign-in, permissions and data protection
- Incident response and remediation advice
Consulting and technical leadership
Support for teams and business owners: technology choices, architecture, code review and running an IT project.
- Contract Tech Lead and architect
- Technical audits and help choosing technology and vendors
- Code review, working standards and mentoring developers
- Turning business needs into a technical plan and estimates
Projects
Systems and sites I have worked on
Selected projects for companies from different industries. Some have been running for years and are continuously developed.
- Custom applicationLiveSince 2017
Pawnshop management system
A comprehensive application for the daily work of a pawnshop, developed and maintained continuously since 2017. It combines loans, consignment and sales with fiscal registers, an online shop and a full CRM.
- Loans and pawn loans with automatic calculation of amounts due and repayment settlement
- Consignment handling and records of accepted goods
- Sales of second-hand goods and jewellery
- Fiscal register support
- Listing products in the WooCommerce online shop straight from the system
- A full CRM covering customers and all of the pawnshop software
- CakePHP
- MySQL
- C#
- WooCommerce
- WordPress
- Custom applicationLiveSince 2025
Transaction verification CRM
An application that verifies cash payments, traditional bank transfers and instant payments against invoices and receipts, with a working integration with the Fakturownia API.
- Cash, traditional transfers and instant payments in one place
- Matching payments with invoices and receipts
- Integration with the Fakturownia API
- CakePHP
- RabbitMQ
- PostgreSQL
- Custom applicationLiveSince 2025
Property management system
A custom application for managing rentals: tenants, agreements, recurring payments, settlements and reports. It replaces manual spreadsheets and deadline tracking.
- Bank statement import with automatic payment matching
- Invoicing and status sync with Fakturownia
- SMS and e-mail notifications processed in the background
- CakePHP
- PostgreSQL
- Redis
- Online shopLive
Bullion and coin shop
A WooCommerce online shop with a custom child theme, connected to a dedicated CRM that keeps prices up to date based on the market.
- CRM with ongoing price updates based on the market
- Product and order data exchange with external systems
- CakePHP
- MySQL
- WordPress
- WooCommerce
- Online shopLive
PrestaShop store for the German market
An online shop on PrestaShop 1.6 serving customers in Germany. Development, fixes and maintenance of an existing site.
- PrestaShop
- PHP
- Company websiteLive
Service company website
Website of a company installing, repairing and maintaining exterior shading systems, with automatic deployment to the server.
- WordPress
- PHP
- Mobile appIn preparation
Mobile app with panoramic crosswords
An in-house project: a Flutter app with an API backend, a database and automated content generation. In preparation.
- Flutter
- Symfony
- PostgreSQL
- Redis
- Docker
- Custom application2015
Car parts CRM
A CRM for selling car parts with an eBay.de integration. It could synchronise several thousand products. Project completed.
- CakePHP
- MySQL
- eBay
- Custom application
Affiliate system for sports betting
An application for settling affiliate codes and running dedicated landing pages. Project completed.
- CakePHP
- PostgreSQL
Projects
Experience from large projects
Large systems and teams I worked with as part of earlier employment.
FinTech and Crypto platform
Architecture and development of a FIAT/Crypto exchange office and an OTC platform for high-volume clients: APIs, payment gateway integrations, transaction security.
Betting operations system
Active involvement in building a system that handles sports betting, as part of long-running work on custom systems. Project management, site maintenance and development.
Settlement system for an association
Taking part in building and developing a system for a non-profit organisation that supports organisations operating at schools, such as parents’ councils and student sports clubs.
Leading teams and projects
Work as Team Leader and Project Manager: sprint planning, code review, quality standards, client contact and turning business needs into technical solutions.
Technologies
Tools chosen for the task
I pick technology to fit the project, not the other way round. This is the ecosystem I work in most often.
Backend
- PHP
- Symfony
- Laravel
- CakePHP
- Node.js
Frontend and mobile
- Vue.js
- Nuxt
- TypeScript
- Tailwind CSS
- Flutter
Data
- PostgreSQL
- MySQL
- Redis
E-commerce and CMS
- WordPress
- WooCommerce
- PrestaShop
Infrastructure and tools
- Linux
- Apache
- Docker
- Git
- GitHub
- GitLab
- GitHub Actions
- Cloudflare
- Visual Studio Code
AI and ML
- GitHub Copilot
- Claude
- OpenAI GPT
- Gemini
- n8n
Collaboration
How I work
A simple process where you always know where things stand.
- 01
Conversation
I learn about your problem, goals and constraints to pick the right solution.
- 02
Scope and estimate
We agree on scope, stages and how we settle, so costs stay predictable.
- 03
Delivery
I work iteratively, show progress and roll out changes in stages.
- 04
Maintenance and growth
After launch I keep the system running and grow it together with your business.
Contact
Let's talk about your project
Describe what you want to build, fix or modernise. I will reply personally and suggest next steps.
Project work and B2B collaboration, remote.
Collaboration in English or Polish.