Customer testimonials

An insight into projects of my clients, review of our collaboration included.
Agile.Coach GmbH & Co. KG, Berlin

Training & Coaching

July 2021 to date, employees 1-10, team language German

Appointment booking system from scratch with PHP / Symfony 5, EasyAdmin, API Platform, React.js, easybill, sendgrid, iCalendar, WordPress Plugins

Dr. Timon Fiddike
Managing Director Agile.Coach GmbH & Co. KG

I met Daniel in 2014 at a meeting of the PHP Usergroup Berlin. The group on that day was small and thus an intensive exchange about software development in the web environment took place. Today I am very happy about this, as we have been working together for more than 15 months now.
During this time he rebuilt a booking system for us based on EasyAdmin and Symfony 5.4, which comfortably covers all critical aspects from booking to invoicing and management.
Previously, our company processed orders with a contact form and a collection of Excel tables. Due to the COVID-19 pandemic, there were a lot of rebookings, so a modern and automated system became necessary.
In the current stage of expansion, we have our own API based on API Platform as well as interfaces to Easybill, Sendgrid, Dropbox, Google Calendar and other systems. Besides EasyAdmin and Symfony in our administration backend, Bootstrap & React are used in the customer area. All together it makes our work much easier and more pleasant and we don't want to do without it anymore.
Depending on the topic we consulted with Daniel via email, phone, video conference or ticket system and always found good solutions. He offers full service from planning / architecture to development and operation of our web application and we are happy that he will continue to support us.

Neopubli GmbH, Berlin

Self-publishing platform, publishing

April to June 2016, employees 10-50, team language English

PHP / Symfony, REST API with FOSRestBundle, Frontend with AngularJS & Bootstrap. Renewal of core flows on the website, migration & refactoring of old Zend Framework 1 code into the new Symfony environment incl. UnitTests. Other technologies: bower, Twig, LESS, RabbitMQ, Jenkins.

Daniel Poschmann
CTO Neopubli GmbH

Daniel Sippel supported our team for two months with the redevelopment of a core feature on our website.

The workbench, where end customers can assemble their print projects and publish them later, was redeveloped using AngularJS on the frontend and Symfony2 FOSRestBundle on the backend. I already knew Daniel from our time together at MyHammer - he had no experience with AngularJS when he started at epubli. He learned how to use it autodidactically during the implementation. He was also able to convince in the backend. He analyzed our old Zend Framework code with a very fast grasp and made sure that the new workbench fits perfectly into the existing environment and that no features were lost.

Furthermore, he also took care of the project management and ensured transparency in the team using Scrum, so that the project progressed well. It was also very good and helpful that he was actively involved in the design and advised and supported our product owner with his expertise. Daniel worked independently and always proactively provided me with the current status, so in the end no wishes were left unfulfilled in terms of quality and quantity. I am completely satisfied with the work done and can recommend him without reservation.

CrossLend GmbH, Berlin

Credit Marketplace, FinTech

December 2014 to July 2015, Employees 50-200 (2015), Company language english

Support of the existing developer team in the area of Symfony backend. Building the administration backend with SonataAdminBundle.

Filipe Garcia
Head of Engineering CrossLend GmbH

Daniel Sippel supported our team in Symfony2 backend development from December 2014 till July 2015. He has a very good knowledge of Symfony and PHP, is reliable and works independent. As a real member of our team he used his deep understanding of apis - server (FOSRestBundle) as well as client side - to get things done. As well, he was the main developer of our internal admin interface, written with the help of SonataAdminBundle. He works very solution-oriented and communicates well with other departments and product owners.

werpflegtwie GmbH, Berlin

Health & Care

June to October 2014, employees 1-10, team language German

Implementation in collaboration with Eatch Interactive and another freelance colleague.
PHP 5.5 & Symfony2, jQuery. Hosting: AWS EC2 Ubuntu, Apache & AWS RDS MySQL.

Together with Daniel Sippel as the main responsible and executing backend developer I have developed the platform from scratch for the last 4 months using Symfony2 (PHP Framework). built. I was and am highly satisfied with his work. He works fast, reliable, explains well, understands quickly, advises competently+helpfully, also takes over project management tasks sometimes.
100 points!