Services
Custom software development for businesses
I build web and mobile applications for businesses that need their own way to manage orders, customers, billing or documents. I connect new software with ERP, CRM and payments, and develop existing systems in stages.
Marek Walczak · IT POMELO · Zielona Góra · remote across Poland
Let's talkService scope
- 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
A dedicated application instead of manual work
A business system can connect staff dashboards, customer records and billing. One example is the pawnshop system developed since 2017: it covers loans, consignment, sales, fiscal registers and listing products in WooCommerce.
ERP, CRM and API integrations
When staff copy data between applications, the starting point is deciding which system owns products, orders and billing. My projects use APIs, webhooks and background tasks, including payment reconciliation and Fakturownia integration.
Developing and modernising existing software
Not every project needs a new application. A code and architecture review helps identify modules to rebuild, upgrades and necessary tests. Staged modernisation separates ongoing development from replacing older technology.
Examples of my work
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
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
Sports club management system
In preparation
A sports club platform in development, comprising a public website, club application, administration panel, API and supporting services.
- Public website, club application and administration panel
- NestJS API and services supporting the platform
- OIDC sign-in and club memberships and roles
- User interface and API messages in Polish, English, Ukrainian and German
Frequently asked questions
- When is custom software worth considering?
- When off-the-shelf tools do not support an important business process or require constant manual data transfers. Start by describing the problem and checking whether an integration or extension of your current application is enough.
- Can you develop an application built by someone else?
- Yes. I review code, modernise and maintain existing applications. The scope follows an assessment of the system, its technology and constraints.
- How much does an application cost?
- Pricing is individual and depends on scope, integrations and the condition of existing software. Describe the process, your current tools and the intended result in your message.
Let's talk about your project
Describe your goal, current systems and the changes you need. We will agree on next steps and an individual estimate. Remote collaboration across Poland, in Polish or English.
Let's talk