Jakub Rozehnal.

Senior PHP/Symfony dev — B2B e-commerce and backend systems

I build robust backend systems for e-commerce and healthcare. TDD, static analysis, and CI/CD are my standard, not a bonus — 7+ years with PHP/Symfony.

About me

I'm a web application developer focused on PHP and the Symfony ecosystem. I have experience designing and building complex e-commerce platforms, insurance tracking systems, and advertising servers. I prefer Test-Driven Development — every feature starts with a test.

I believe quality software comes from clean code, automated tests, and continuous integration. That is why I advocate for PHPUnit, PHPStan, and CI/CD pipelines in all my projects.

TDD approach

Test first, code second. Every feature is covered by tests.

Code quality

PHPStan, CodeSniffer, and code reviews are part of my workflow.

DevOps

Docker, Kubernetes, CI/CD — automation from development to deployment.

Services

Presentation websites

Custom presentation websites and landing pages — from a simple business card to multilingual corporate sites with SEO, contact forms, and structured data. Focus on load speed, accessibility (a11y), responsive design, and clean code without framework overhead. This site itself is a live example.

Backend development

Design and implementation of server-side logic in PHP (Symfony, Laravel). REST APIs, third-party integrations, database query performance tuning, and domain logic design with testability in mind.

E-commerce solutions

Custom B2B and B2C e-commerce platforms. Comprehensive solutions from product catalog through cart and payment gateways to ERP and invoicing integrations. Experience migrating legacy solutions to modern Symfony.

Application modernization

Migration of legacy PHP applications to modern frameworks (Symfony, Laravel). Introducing automated tests (PHPUnit, Codeception), static analysis (PHPStan), code review processes, and CI/CD pipelines without production downtime.

DevOps & infrastructure

Application containerization (Docker), orchestration (Docker Swarm, Kubernetes), CI/CD pipeline setup, monitoring via Grafana/Prometheus, and alerting. Experience migrating from load-balanced setups to Swarm with a 120 req/s peak.

Case study: E-commerce Docker Swarm

Migrating a B2B/B2C e-commerce platform from LB setup to a containerized cluster

Challenge

Original setup: two application servers behind a load balancer, deploy via rsync, no environment reproducibility. During peaks the system choked and rollbacks were painful.

Solution

Containerization of the application (PHP/Symfony), move to a Docker Swarm cluster with rolling updates. Introduced Grafana + Prometheus for metrics and alerting. CI/CD pipeline with automatic deploys on merge to main.

Result

Stable response time of 1–1.5 s even at a 120 req/s peak. Rolling deploys via Docker Swarm, rollbacks within seconds. Full metrics and alerting cut MTTR on incidents by more than half.

Experience

2023 — present

Web Developer

GT Software s.r.o.

Building a system for processing medical insurance claims for doctors in the US. Heavy use of AI in development frees up capacity for additional external projects.

2021 — 2026

Lead Developer

U&Sluno a.s., Ostrava

Lead developer of a complex B2B/B2C e-commerce platform. Dockerizing the application, migrating legacy PHP to Symfony, implementing PHPStan, Codeception, and CI.

2019 — 2021

Web Developer

VLTAVA LABE MEDIA a.s.

Development and maintenance of an automotive advertising server using Symfony.

2017 — 2019

First programming experience

Exact Systems Czech Republic s.r.o.

Building an internal OHS system in PHP and process automation in VBA. My first hands-on programming experience in a real production setting.

Technologies

Backend

  • PHP
  • Symfony
  • Laravel
  • Doctrine
  • OpenAPI Specification
  • Strapi.io

Testing & quality

  • PHPUnit
  • PHPStan
  • CodeSniffer
  • Codeception
  • Cypress

Databases

  • MySQL
  • PostgreSQL
  • Redis
  • MongoDB

DevOps & tools

  • Docker / Docker Compose
  • Kubernetes
  • CI/CD
  • Git
  • Linux (Debian)

Frontend

  • HTML / CSS (SCSS)
  • JavaScript
  • Next.js

Legacy & Modernization

  • jQuery
  • Webpack Encore
  • VBA
  • Legacy PHP migrations

Contact

Have a project I can help with? Schedule a short call or send me a message.

Write to me