This is the first Toastmaster speech I gave at my Toastmaster club. It was in 2011 and I didn't have the habit to post my speeches on my blog at the time.

I am sure some of the work I have done, has had an impact on your life. This impact maybe invisible, small and indirect; but it is a growing impact not just on your life but on the life of hundreds millions or even billions of people. In this speech I will explain to you why.

As a teenager, I knew I wanted to become an engineer. I liked to play with lego blocks. I liked to take things apart to see how they worked. I liked to design on paper new things like flying cars. By being an engineer I could make the world a better place, because using better products would improve people's lives.

In the mid 1980s computers started to become affordable and I soon realized that they were the future of engineering. So I convinced my parents to buy me one. I started to learn how computers worked and how to program. I was fascinated by programming languages and other software tools that helped people "talk" to computers, and make them do what they wanted. My hobby of developing software tools started then.

I wanted to become an engineer and I managed to get into an engineering school. There I studied computer science, and I got my first job as a software developer 15 years ago. Since then I have been working as a software engineer. I worked on software for medical applications (to see a foetus in 3 dimensions), for banks, and for the military. I even wrote the official iPhone application for the Olympique Lyonnais soccer team, but it is not this software that has had the biggest impact.

My hobby and passion for software development tools guide me throughout my professional career. In my free time, I learned about the Linux operating system. Since Linux is open source software I could freely use and develop the tools running on it. My Linux hobby helped me get work.

The Linux operating system, also simply called Linux, was created 20 years ago by a Finnish guy called Linus Torvalds. He was a student at the time and is still developing it. Linux is developed by thousands of developers from all over the world. Many of them are now employed by companies like Google, Intel, Hitachi, SFR, and so on.

In 2005 Linus Torvalds created a software called Git to manage the source code of Linux. What do I mean by source code? It is the set of files and instructions in these files that make up the program. It is very important to have good tools to manage the source code, especially when many people are working on the same software. In 2006 I started to work on Git as a hobby. I became the 12th developer of Git in the world, and the first one in France in terms of the number of changes. Git, like Linux, has been a tremendous and growing success. Many companies like Google, Yahoo, Intel, Facebook and Twitter, are using Git.

For example, since the Google operating system for smartphone called Android is based on Linux, many people developing applications for this operating system are now using Git. The latest versions of Apple development tools now use Git as the default source control tool. This means that many iPhone, iPad and Mac applications have been developed using Git and many more will be during the coming years.

Just as my Linux hobby in general helped me with my career, so did my Git hobby. I have given presentations about Git, one in Dresden Germany in 2009 and one at a Google Conference in India last October. I will give another one next August in Vancouver Canada at the biggest Linux Conference ever. There we will be celebrating 20 years of the Linux system.

What is really exciting is that the improvements I made to Git are like seeds that have grown, are still growing, and are now bearing many small fruits of many kinds in invisible ways. These improvements make the software developer's job easier. For example, some of the improvements I made help them find bugs.

This means that people using the applications or operating systems made by these developers have a better user experience. And since software is everywhere nowadays, in the end it means a better user experience for nearly everybody. When I take the metro and I see people using their smartphone, I like to think that perhaps a small part of the quality of the experience they get comes from the work I did on Git. I feel that I succeeded in making many people's lives a little better.