Lennart Hengstmengel

I am an experienced web developer specialized in server sided technology. After more than 20 years of professional experience at various employers, I decided to go freelance in October 2021. You can read about me and my background here. If you think I might be able to help you, get in touch!

What I do


Design, building and implementation of new applications and databases. Maintenance, enhancement, refactoring and bugfixing of existing applications.


Integration of APIs, web services and other applications like financial or CRM software. Design and implementation of solid and well documented APIs to make your own data and applications available to others.


Webhosting, databases, application servers, firewalls, load balancers. Setup, configuration and management. Stable and scalable; in the cloud, virtualized, or on your own hardware.

Consultancy and support

I can help you with tailor made advice and consultancy. I provide all needed support and I can take care of end user training.

My tools

Server sided languages

I have been using PHP since version 4. Back then the language was not really suited for complex applications. I discovered Perl, a powerful but often misunderstood language. With the passing of time, the usage of Perl has diminished, and I found myself getting back to modern PHP versions. I also discovered Python, which is widely regarded as a modern successor.

PHP frameworks

PHP really shines when combined with a powerful framework like Laravel, which is partly Symfony based but much more than that. It makes creating well structured and solid applications a breeze. Since February 2021 I am a certified Laravel developer.


Javascript is everywhere, not just in the browser anymore. It runs on servers and has a very important role in development environments. Frameworks like Vue.js and React are indispensable, even for backend developers like me.

Operating systems

While MacOS is quite nice, I prefer working with Ubuntu Linux. Not only as server platform, but also on my desktop and laptop. It is the perfect open development platform. The power of the command line interface combined with the GUI provides me with everything I need and more.

Web server

Apache used to be the gold standard among the web servers, but nowadays that place has been taken by Nginx, which has a lighter footprint and easier configuration.


Most data really is hierarchical and relational. So it makes sense to use a relational database MySQL. However there are certain use cases for a no sql database, in which case I use MongoDB.

Cloud services

Virtualization really has become a big thing, everything seems to be "in the cloud". I have good experiences with various AWS services by Amazon. But "vendor lock in" can be a risk too. That is why I prefer to stay away from proprietary, closed systems, and use open source as much as possible.