Backend
PHP 8, Laravel, APIs, MySQL/MariaDB, refactoring, roles and permission models
Senior Full-Stack PHP Developer
Senior Full-Stack Developer for PHP, Laravel, Vue/TypeScript, and stable business web systems.
I develop, modernize, and operate web applications where backend, frontend, data, support, and operations belong together - with experience from enterprise e-commerce, ISHAP, CANCOM/K-Businesscom, Schrack Technik, and my own infrastructure.
Currently open to permanent roles / Full-Stack PHP / Laravel / Vue.js / Vienna or hybrid
- PHP 8, Laravel, APIs, MySQL/MariaDB, and modernization in live systems
- JavaScript, TypeScript, Vue.js/React, and product-oriented web interfaces
- Linux, hosting, deployments, support awareness, and controlled AI usage
Current product work: HostingCenter.at - managed hosting, website agent, website checks, and AI-supported support.
Job Fit
A good fit for roles around full-stack business web development
Experience as a full-stack web developer: business projects in the software environment of large companies.
Frontend
JavaScript, TypeScript, Vue.js/React, responsive interfaces, product-oriented UI implementation
Operations
Linux, Apache/nginx, deployments, hosting, SSL, troubleshooting, performance
Working Style
clarifying requirements, understanding existing systems, keeping live operations stable, using AI tools with control
Selected organizations
Professional background and project contexts
Schrack Technik, CANCOM, Kapsch, ISHAP, ÖGB/ÖGJ
Profile
Profile at a Glance
I am a Senior Software Developer focused on long-lived web applications, interfaces, databases, operations, and product logic.
I work especially well in environments where existing systems need to be understood, modernized, extended, and operated reliably.
I am currently working on HostingCenter.at, a managed hosting and website platform that combines classic web infrastructure with AI-supported analysis, content preparation, and controlled approval processes.
Former stations include Schrack Technik, CANCOM/K-Businesscom, Kapsch, and ISHAP.
Relevant roles
- Senior Full-Stack PHP Developer
- Laravel / Vue.js Developer
- Business Application Developer
- Application / Platform Engineer
- interface between business, development, and operations
What I bring
- technical ownership from feature to operation
- experience with enterprise web systems and PHP modernization
- understanding of APIs, databases, and interfaces
- hosting, Linux, and support awareness
- structured requirements analysis
- pragmatic implementation with maintainability in mind
Current Focus
Technical areas where I am currently especially effective.
In practice they overlap: existing web systems, operations, product logic, and the controlled use of new tools.
Business Web Systems
Understanding, extending, and modernizing existing applications without putting live operations under unnecessary strain.
Product and Support Awareness
Clarifying requirements, reproducing issues, including the user perspective, and implementing pragmatic technical solutions.
AI-Supported Development
I use AI tools for research, prototyping, and routine work. Architecture, quality, security, and integration remain controlled technical decisions.
Web Infrastructure
Hosting, deployments, APIs, access, and the part that has to stay stable at night are part of software work for me.
Skills
Skills & Technical Focus
My work sits at the intersection of development, architecture, operations, and product logic. I come from web development, but I think strongly in systems, interfaces, and long-term operation.
Backend & Architecture
- PHP 8, Laravel, OOP, and procedural legacy systems
- MySQL / MariaDB
- REST APIs, web services, middleware
- refactoring and modernization of existing systems
- roles, permissions, and access concepts
- maintainability, performance, and technical structure
Frontend & Web
- HTML5, CSS3, JavaScript ES5 / ES6
- jQuery, AJAX, Vanilla JS
- Bootstrap and responsive UI implementation
- TypeScript, Vue.js, React, and Tailwind in current projects
- browser-based workflows and product-oriented interfaces
Infrastructure & Operations
- Linux, Debian, Ubuntu
- Apache, nginx, web server and hosting setups
- Bash, cron jobs, automation
- deployment, operational awareness, and technical ownership
- Git / GitHub
- Docker and CI/CD basics
Interfaces, Data & Integration
- API integration and interface logic
- data models and database work
- OAuth / authentication concepts
- performance, caching, CDN, and optimization
- security, SSL, data protection, and access control
Working Style & Tools
- requirements analysis and technical concept work
- documentation and structured handover
- Jira, Confluence, Scrum / agile workflows
- collaboration with business teams, customers, and external partners
- second-level-style analysis and troubleshooting
- AI-supported research, prototyping, and delivery with technical control
AI Systems, Agents & Emerging Technology
- hands-on work with LLMs, AI-supported development, and agentic workflows
- own agent setups in controlled server-side test environments
- technical evaluation of AI tools beyond simple chat usage
- work with prompting, context design, tool use, and domain-specific workflows
- audio-related AI experiments around stem separation, voice tools, and workflow automation
- concept work for an agentic hosting product focused on administration, permissions, security, and operational logic
- careful handling of limits, failure modes, data protection, and human control
Application & Business Focus
- operation and further development of existing applications
- translation of business requirements into technical solutions
- stability, performance, and process improvement
- interfaces between software, users, and operations
- cost-benefit thinking from long-term self-employment and entrepreneurship
Selected Work
Selected roles and projects from business web development, operations, and product work.
Not a full archive. A compact selection of professional stations, live systems, and own product ideas.
Business / Platform / Web Development
Professional roles, platform work, and managed web systems
What it is: Work on a large enterprise webshop platform with 18 country instances.
Why it matters: PHP modernization of legacy parts to PHP 8.2, API work, refactoring, and stability in a live system.
My role: Senior PHP development focused on maintainable implementation, data and interface logic, and technical analysis of existing structures.
Short description: AI-supported managed hosting and website care platform for SMEs.
What it is: HostingCenter combines managed hosting, website support, website checks, domain workflows, and an AI-supported HostingAgent. The goal is not blind autopilot, but a controlled process of analysis, proposal, technical preparation, and human approval.
Why it matters: The project connects web development, hosting, Linux operations, product logic, permissions, admin flows, customer value, automation, and AI-supported implementation.
My role: Product concept, technical architecture, frontend/backend logic, hosting and operations model, website audit ideas, agent workflows, trust and approval processes.
What it is: Full-stack web development in a business software environment with PHP and JavaScript.
Why it matters: Product-oriented work on existing applications where business requirements, data, UI, and operations come together.
My role: Implementation and extension of web applications with a focus on clarity, stability, and day-to-day usability.
What it is: Custom solutions close to hosting, servers, operations, and web applications.
Why it matters: Roles where troubleshooting, infrastructure understanding, customer/support proximity, and development practically overlap.
My role: Technical support, development, and analysis at the interface between application, operations, and infrastructure.
Product / Audio / Own Projects
Own product work, audio tools, and selected websites
What it is: A self-hosted platform for audio sessions with customer access, playlists, playback, and clear roles.
Why it matters: The system is live in production; media, permissions, workflow, and responsibility have to line up cleanly.
My role: Product logic, system structure, access model, technical implementation, and ongoing operation.
What it is: Platform work around websites, content, media logic, and managed web presences.
Why it matters: The project shows product-oriented web development for recurring needs instead of one-off websites without an operations model.
My role: Structure, frontend/backend logic, reusability, content flows, and technical care.
What it is: A browser-based audio workflow built on APIs around stem separation, voice tools, LLM-supported audio processing, and DAW-adjacent automation.
Why it matters: The interesting part is not the individual AI feature, but whether it becomes a tool that holds up in real workflows.
My role: Product concept, workflow design, API integration, and AI-supported audio experiments within a controlled technical frame.
What it is: Internal plugin concepts, mostly around tuner and modulation tools, with a possible later release perspective.
Why it matters: With tools like these, the idea itself is not enough; interaction and technical precision have to work in day-to-day use.
My role: Use case, interaction logic, and technical frame before it can become a product.
What it is: A substantial band website with controlled support for ongoing operations, content maintenance, and editorial structure.
Why it matters: An example of a custom solution that uses modern tools while still staying technically controllable.
My role: Concept, technical structure decisions, and implementation from prototyping to go-live.
What it is: The live public website karlhorak.com, including a production audio player.
Why it matters: A public website where structure, frontend implementation, media logic, and production readiness have to work together.
My role: I handled the technical implementation from structure to frontend and brought it to production readiness.
Vita
Vita in Brief
2024 - 2025
Schrack Technik GmbH
PHP Senior Software Developer in an enterprise e-commerce environment. Work on a large webshop platform with 18 country instances, API development, refactoring, and PHP modernization from PHP 5 to PHP 8.2 in a live system.
2023 - 2024
Kapsch / K-Businesscom / CANCOM
Senior Software Developer in custom solutions. Focus areas included hosting, servers, DevOps-adjacent work, web applications, technical support, and operations.
2021 - 2023
ISHAP Softwareentwicklung GmbH
Full Stack Web Software Developer focused on PHP, JavaScript, and web applications.
2003 - 2025
goodconnect IT Services e.U.
Self-employed work in web, software, and custom solutions. Delivery of many projects of different sizes for SMEs, organizations, and larger customer environments.
2014 - today
Bigfield Tonstudio & Audio Services
Audio, studio, and product work with technical ownership. Today this is especially relevant at the intersection of audio workflows, software, web technologies, and internal product ideas.
YaWK / yawk.io
Own CMS/web kit
Own CMS/web kit with module and plugin architecture, developed over many years and used as the basis for numerous websites. Documented pre-AI legacy work on GitHub.
How I Work
I sort out the system first. Then I build.
I am most useful when the work is not just about a screen, but about what should be built, how it fits together, and what has to hold up once people actually use it.
Before the build starts
I clarify the problem, the boundaries, the interfaces, and the operating model early. That saves expensive churn later.
Structure that lasts
Shipping fast matters. So does having a structure that does not fall apart after the second release.
Product and system belong together
User flow, API contracts, data, permissions, and infrastructure are usually the same conversation. I treat them that way.
AI is a tool
I use AI where it genuinely adds speed. I do not hand off architecture, quality, integration, or final judgment.
Background
What my work is built on.
I have worked on enterprise e-commerce systems across 18 country instances. That included PHP modernization, API integration, performance work, and the less glamorous question of how a live system stays maintainable.
I host my own sites and client sites in a virtual datacenter setup. That means I naturally think about operations, reliability, access, and what happens after launch.
YaWK was a long chapter and it mattered. It teaches you a lot when you carry a system over years instead of shipping a release and moving on.
Audio and studio work sharpen my product judgment. Signal flow, interaction, responsiveness, and technical detail all have to work together.
This mix of development, operations, infrastructure, product work, and entrepreneurship is why I do not see technical roles as implementation only. I care whether a system works in day-to-day use, remains maintainable, and is usable for people who did not build it themselves.
Emerging technologies interest me when they become practically useful. With AI and agents, I am less interested in the next hype term and more interested in how such systems can be integrated safely, operated with control, and connected to real workflows.
Contact
Contact for suitable full-stack roles and technical conversations.
I am currently interested in permanent roles around PHP 8, Laravel, Vue.js/TypeScript, MySQL, Linux, business web systems, product care, and operations.
I am open to conversations about roles where development, existing systems, support awareness, and technical ownership come together.
Talk about a role
- Full-stack PHP, Laravel, and business web development
- Vue.js, TypeScript, and product-oriented interfaces
- MySQL/MariaDB, APIs, and interfaces
- Linux, hosting, operations, and troubleshooting
Talk about website & hosting
- Website, hosting, or technical care for SMEs
- Website checks, performance, SSL, DNS, and operational questions
- AI-supported content preparation and analysis with approval
- Managed hosting and ongoing website care through HostingCenter.at
Direct contact
- Email danielretzl@gmail.com
- LinkedIn linkedin.com/in/danielretzl
- Phone +43 676 9094197
- Location Austria