Freelance Software Developer | Simplicity Networks GmbH
Simplicity Networks GmbH
Schlagwörter
Skills
Verlässliche Fullstack-Softwareentwicklung seit 2006. Solide Backend-Entwicklung, Datenbanken und Infrastruktur.
PHP, Symfony, Java, JavaScript, CSS, PostgreSQL, MySQL, MariaDB, AWS/GCP/Azure Cloud, Docker, Linux, Gitlab-CI.
Fokus auf Barrierefreiheit (Accesibility, a11y) insb. im Hinblick auf den EAA (European Accessibility Act) 2025 und WCAG-Richtlinien.
Entwickler einer großen SaaS-Plattform für Venture Capitals. Beratung und Coaching in allen Implementierungsfragen.
Entwicklung von Grund auf (Greenfield) für MVP-Projekte oder große Softwaresysteme.
Wartung und Instandhaltung etablierter Software.
Migrationen von Altsystemen, Daten und Prozessen. Code-Upgrades von Systemen und Komponenten.
Coaching zu den Themenbereichen PHP, Automatisiertes Testing, Continuous Deployment / Delivery, SQL + Datenbankarchitektur
Interim Team Lead für Ihr Software-Team das sich im Aufbau oder im Wechsel befindet.
PHP, Symfony, Java, JavaScript, CSS, PostgreSQL, MySQL, MariaDB, AWS/GCP/Azure Cloud, Docker, Linux, Gitlab-CI.
Fokus auf Barrierefreiheit (Accesibility, a11y) insb. im Hinblick auf den EAA (European Accessibility Act) 2025 und WCAG-Richtlinien.
Entwickler einer großen SaaS-Plattform für Venture Capitals. Beratung und Coaching in allen Implementierungsfragen.
Entwicklung von Grund auf (Greenfield) für MVP-Projekte oder große Softwaresysteme.
Wartung und Instandhaltung etablierter Software.
Migrationen von Altsystemen, Daten und Prozessen. Code-Upgrades von Systemen und Komponenten.
Coaching zu den Themenbereichen PHP, Automatisiertes Testing, Continuous Deployment / Delivery, SQL + Datenbankarchitektur
Interim Team Lead für Ihr Software-Team das sich im Aufbau oder im Wechsel befindet.
Projekthistorie
04/2024
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04/2024
Integration of a 3rd-party PLM system into legacy systems (FashionXL) via XML/SOAP. Development of an
event-driven architecture built on Kafka, aggregating data into an in-house PIM system. Adaptation of AWS CDK
(Cloud Development Kit) into the team to facilitate architecturing data product pipelines across teams, defined in
code. Building data contracts validated by JSON Schema to facilitate JSON-based REST communication between
microservices written in Golang and TypeScript.
⇒ PHP (Zend, Laminas), Python, Golang, Postgres, MSSQL, AWS (Kubernetes, Lambda), Docker, Kafka, SOAP.
event-driven architecture built on Kafka, aggregating data into an in-house PIM system. Adaptation of AWS CDK
(Cloud Development Kit) into the team to facilitate architecturing data product pipelines across teams, defined in
code. Building data contracts validated by JSON Schema to facilitate JSON-based REST communication between
microservices written in Golang and TypeScript.
⇒ PHP (Zend, Laminas), Python, Golang, Postgres, MSSQL, AWS (Kubernetes, Lambda), Docker, Kafka, SOAP.
03/2022
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03/2024
Freelance Software Developer | Limetec Biotechnologies GmbH
Limetec Biotechnologies GmbH
Modernization of a legacy codebase by code modularization, cleanup and refactoring using PHPStan, CodeSniffer,
and Rector. Implementation of client management functionality, modularizing and integrating within the legacy
codebase (TypeScript, React). Upgrade PHP 7.4 codebase to PHP 8.2, ensuring smooth upgrades of incompatible
dependencies.
⇒ PHP (Symfony), MySQL, LATEX, Acroforms. TypeScript, React.
and Rector. Implementation of client management functionality, modularizing and integrating within the legacy
codebase (TypeScript, React). Upgrade PHP 7.4 codebase to PHP 8.2, ensuring smooth upgrades of incompatible
dependencies.
⇒ PHP (Symfony), MySQL, LATEX, Acroforms. TypeScript, React.
12/2021
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02/2024
CEO | Code & Magic UG
Code & Magic UG
Led a B2B web design agency with a team of 5 to create conversion optimized landing pages and CMS integrations for
SMBs. Managed projects from inception to delivery (agile/”scrumban” methodology). Hired, trained and managed
developers and office staff.
Outbound and inbound sales, outreach, and customer expectation management.
⇒ Golang, PHP (Symfony), PostgreSQL, Pimcore, htmx.
SMBs. Managed projects from inception to delivery (agile/”scrumban” methodology). Hired, trained and managed
developers and office staff.
Outbound and inbound sales, outreach, and customer expectation management.
⇒ Golang, PHP (Symfony), PostgreSQL, Pimcore, htmx.
01/2020
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09/2020
Freelance Software Developer | VGL Verlagsgesellschaft mbH / vergleich.org
VGL Verlagsgesellschaft mbH / vergleich.org
Support the team with migration to AWS servers (S3, EC2), infrastructure growth by leveraging an in-house Event
Sourcing implementation.
Runtime profiling and optimization by reducing SQL query complexity and/or offloading workloads to the DB.
⇒ PHP, MySQL, PHPStan, Psalm, Redis, AWS, Blackfire Profiler.
Sourcing implementation.
Runtime profiling and optimization by reducing SQL query complexity and/or offloading workloads to the DB.
⇒ PHP, MySQL, PHPStan, Psalm, Redis, AWS, Blackfire Profiler.
11/2017
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12/2019
CTO | Sompani UG
Sompani UG
Greenfield implementation of a marketplace for candidate referrals used by 500+ companies.
Created an internal profile management tool leveraging Pimcore. Optimized User Exprience by involving Server-Side
Rendering, keeping the TTFB response rates <150ms, and leveraging HTMX for user-interactive AJAX requests,
keeping the added TTI (Time To Interactive) below 20ms.
DevOps: Established a CI/CD pipeline based on industry-standard best practices, allowing for up to 10 zero-downtime
deployments to production per hour, staging and QA environments.
Unit Testing and fully automated browser-based functional testing triggered via code commits by the team using GitLab
CI minimizes human error during development. Database Schema migrations using Flyway. Hybrid cloud/bare-metal
server infrastructure. (AWS, Google Cloud, Arch Linux natively on on-premise servers).
Image delivery and transformation via headless Inkscape and Cloudinary CDN API.
Scraping of 20 different ATS (Applicant Tracking System) providers in addition to API integrations for job listing
imports and candidate exports. Data Mining and extraction from crawled job postings and candidate profiles. Algorithm
design to find the best-performing overlap of auto-extracted vacancy requirements and candidate skills.
⇒ Golang, PHP, Symfony, Pimcore, PostgreSQL, Python, Intercooler.js.
Created an internal profile management tool leveraging Pimcore. Optimized User Exprience by involving Server-Side
Rendering, keeping the TTFB response rates <150ms, and leveraging HTMX for user-interactive AJAX requests,
keeping the added TTI (Time To Interactive) below 20ms.
DevOps: Established a CI/CD pipeline based on industry-standard best practices, allowing for up to 10 zero-downtime
deployments to production per hour, staging and QA environments.
Unit Testing and fully automated browser-based functional testing triggered via code commits by the team using GitLab
CI minimizes human error during development. Database Schema migrations using Flyway. Hybrid cloud/bare-metal
server infrastructure. (AWS, Google Cloud, Arch Linux natively on on-premise servers).
Image delivery and transformation via headless Inkscape and Cloudinary CDN API.
Scraping of 20 different ATS (Applicant Tracking System) providers in addition to API integrations for job listing
imports and candidate exports. Data Mining and extraction from crawled job postings and candidate profiles. Algorithm
design to find the best-performing overlap of auto-extracted vacancy requirements and candidate skills.
⇒ Golang, PHP, Symfony, Pimcore, PostgreSQL, Python, Intercooler.js.
08/2018
-
09/2018
Freelance Software Developer | KostümKollektiv e.V.
KostümKollektiv e.V.
Migrate old PHP4/5 codebase of a costume rental store to PHP7; audit code for secruity vulnerabilities and fix those.
Migrate code to a Service-Oriented Architecture (SOA) using the Mikado Technique.
Add End-to-End tests and unit tests for the legacy codebase using Codeception. Add custom functionality as customer
desires. Ongoing maintenance and hosting.
⇒ PHP4, PHP5, PHP7, JavaScript, Codeception
Migrate code to a Service-Oriented Architecture (SOA) using the Mikado Technique.
Add End-to-End tests and unit tests for the legacy codebase using Codeception. Add custom functionality as customer
desires. Ongoing maintenance and hosting.
⇒ PHP4, PHP5, PHP7, JavaScript, Codeception
08/2018
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08/2018
Freelance Software Developer | LanyBook GmbH
LanyBook GmbH
Shopware upgrade and maintenance, TLS certificate setup, plugin and theme upgrades and customizations.
⇒ Shopware, PHP, ExtJS, Smarty
⇒ Shopware, PHP, ExtJS, Smarty
05/2018
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05/2018
Freelance Software Developer | LayoutBuddy Software GmbH
LayoutBuddy Software GmbH
Upgrade a Shopware plugin code base in order to make it run on the upgraded Shopware 5.4.
⇒ Shopware, PHP 7.2, ExtJS, Smarty
⇒ Shopware, PHP 7.2, ExtJS, Smarty
01/2016
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12/2017
Freelance Software Developer, Interim Team Lead | VGL Verlagsgesellschaft mbH / vergleich.org
VGL Verlagsgesellschaft mbH / vergleich.org
Led a growing team during a progressive modernization of a Wordpress-based site infrastructure to a microservice
architecture based on Symfony 3, facilitating a separate frontend in Vue.js. TDD coaching and process implementation.
Architecture design and implementation.
Optimized database schemata and query infrastructure to facilitate 3mln. visits / day. Integration of Cloudinary image
delivery CDN. API integration to E-Commerce partners connexity.com, guenstiger.de, billiger.de. Amazon
MWS/AWS API integration. Research and implementation of reliable crawling/scraping algorithms for Amazon.
⇒ PHP, Symfony 3+4, MySQL, Intercooler.js, RESTful APIs.
architecture based on Symfony 3, facilitating a separate frontend in Vue.js. TDD coaching and process implementation.
Architecture design and implementation.
Optimized database schemata and query infrastructure to facilitate 3mln. visits / day. Integration of Cloudinary image
delivery CDN. API integration to E-Commerce partners connexity.com, guenstiger.de, billiger.de. Amazon
MWS/AWS API integration. Research and implementation of reliable crawling/scraping algorithms for Amazon.
⇒ PHP, Symfony 3+4, MySQL, Intercooler.js, RESTful APIs.
10/2015
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10/2016
Senior Software Developer | Medici Living Digital Services GmbH
Medici Living Digital Services GmbH
Greenfield implementation of an E-Commerce flat share booking site. Development of an administrative back office for
customer and property management via Sonata Admin Bundle and AdminLTE. Migration of features from a legacy
MVP developed in Zend Framework 2, MySQL, and Drupal to a modular, Symfony-based microservice architecture.
Introduced Pimcore as a multi-language flat exposé authoring platform. Integrated the payment providers Paymill and
Adyen. PHP, JavaScript, REST API. Developed and documented a RESTful public-facing API for B2B partners.
⇒ Java (OpenJDK, Spring Boot), PHP+Symfony, MySQL, MariaDB, PostgreSQL. API interface to a ReactJS client.
customer and property management via Sonata Admin Bundle and AdminLTE. Migration of features from a legacy
MVP developed in Zend Framework 2, MySQL, and Drupal to a modular, Symfony-based microservice architecture.
Introduced Pimcore as a multi-language flat exposé authoring platform. Integrated the payment providers Paymill and
Adyen. PHP, JavaScript, REST API. Developed and documented a RESTful public-facing API for B2B partners.
⇒ Java (OpenJDK, Spring Boot), PHP+Symfony, MySQL, MariaDB, PostgreSQL. API interface to a ReactJS client.
01/2015
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12/2015
Senior PHP Developer | Wine in Black GmbH
Wine in Black GmbH
Implementation of a recommendation algorithm based on customer’s shopping history. Memory usage reduction for
CSV and XML file exports by 64%, as well as other significant optimizations. Design and implementation of an
algorithm to automate voucher code generation and validation.
⇒ LEMP stack, Zend Framework 1+2, Doctrine
CSV and XML file exports by 64%, as well as other significant optimizations. Design and implementation of an
algorithm to automate voucher code generation and validation.
⇒ LEMP stack, Zend Framework 1+2, Doctrine
01/2011
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12/2015
Web Developer | Südwest Presse Online-Dienste GmbH
Südwest Presse Online-Dienste GmbH
Introduced a CSS framework based on Object-Oriented CSS for a web site relaunch in 2012, reducing file size of
included CSS files over 30% and significantly slowed growth of the necessary CSS instructions while the project grew.
Developed a PHP based adapter solution for a legacy authentication system (REST/JSON ↔ SOAP/XML) for the
publisher’s ePaper software.
Co-developed and maintained templates and plugins for fCMS, a 3rd-party CMS specifically built for the publishing
industry, in HTML5+CSS3, PHP and JavaScript.
Developed Wordpress plugins and themes for several of the publisher’s long-form storytelling projects (story-
telling.swp.de/spielraum, storytelling.swp.de/mauerfall, storytelling.swp.de/karlsplatz) and contributed to existing
open-source plugins ([1], [2]); provided coaching and support for the journalists.
Initiated Unit Testing and Test Driven Development with PHPUnit, XDebug, and browser test automation via
NightmareJS/PhantomJS
Introduced graceful degradation for swp.de to optimize rendering in legacy browsers (Internet Explorer 8 and 9)
Introduced git to retire CVS
included CSS files over 30% and significantly slowed growth of the necessary CSS instructions while the project grew.
Developed a PHP based adapter solution for a legacy authentication system (REST/JSON ↔ SOAP/XML) for the
publisher’s ePaper software.
Co-developed and maintained templates and plugins for fCMS, a 3rd-party CMS specifically built for the publishing
industry, in HTML5+CSS3, PHP and JavaScript.
Developed Wordpress plugins and themes for several of the publisher’s long-form storytelling projects (story-
telling.swp.de/spielraum, storytelling.swp.de/mauerfall, storytelling.swp.de/karlsplatz) and contributed to existing
open-source plugins ([1], [2]); provided coaching and support for the journalists.
Initiated Unit Testing and Test Driven Development with PHPUnit, XDebug, and browser test automation via
NightmareJS/PhantomJS
Introduced graceful degradation for swp.de to optimize rendering in legacy browsers (Internet Explorer 8 and 9)
Introduced git to retire CVS
Reisebereitschaft
Verfügbar in den Ländern
Deutschland, Österreich und Schweiz
