The context
MATMAK was already in production when I joined, with real customers depending on it every day. The job is not a rewrite. It is to extend an established application safely: add capabilities, modernise what customers see, and keep the platform fast and stable.
The product combines user accounts, subscriptions, invoicing, pricing, credits, a large catalogue of vehicle patterns, cutting operations, a customer-facing site and an administration back office.
Team product. I contribute to an existing platform alongside the engineering team. The work below is my part of it, not a claim to have built MATMAK alone.
What I build
- Extend ASP.NET Core REST APIs, Razor Pages, services and business workflows.
- Work on authentication, subscriptions, invoicing, pricing, credits and cutting operations.
- Redesigned the customer-facing pages and the administration interface into a modern, responsive UI connected to the existing services.
- Integrated Stripe one-time payments, recurring subscriptions, invoicing and webhook-driven payment status updates.
- Work directly with management and the team on requirements, priorities and releases.
How the system fits together
The solution is a modular, multi-project .NET codebase. This is the part of each layer I work on:
| Layer | What I do | Tools |
|---|---|---|
| Interfaces | Customer pages and the admin back office, redesigned for a modern, responsive experience. | Razor Pages · HTML · CSS · JS |
| Application | APIs, services and workflows for accounts, subscriptions, invoicing, pricing, credits and cutting. | C# · ASP.NET Core · Web API |
| Payments | One-time and recurring payments, invoices, webhook status updates. | Stripe |
| Data | Schema design, query tuning, production databases and backups. | SQL · EF Core · LINQ |
| Operations | Servers, deployments, staging, monitoring and alerts. | Linux · AWS · Nginx · GitHub Actions · Grafana |
The codebase is split into API, Client, Admin, Models and Services projects, which keeps each concern separate and reusable.
Making the data layer faster
Some read and write paths were slower than they needed to be. I redesigned parts of the database schema to remove redundant tables and costly joins, and tuned the Entity Framework Core queries that hit them.
Result: about 40% faster on the affected read and write operations.
Running it in production
My role goes beyond application code. I hold end-to-end responsibility for the company's infrastructure: cloud accounts, servers, production databases, domains, DNS, email and payment services.
- Provision and harden Linux cloud and VPS servers: SSH access, firewalls, Nginx reverse proxy, TLS and application runtimes.
- Administer AWS EC2, production databases, automated backups and a separate staging environment.
- Automate builds and deployments with GitHub Actions.
- Built monitoring with Prometheus, Grafana, Loki and Promtail, with dashboards and alerts across servers, APIs, Nginx and application logs.
Internal addresses, customer data and security settings are deliberately left out of this page.
What this shows
How I work inside an established product: understand the constraints, extend business-critical workflows without breaking them, connect interface and backend changes, and stay accountable through deployment and monitoring.