Developer Interview : Markus Mohrhard

Coding LibreOffice to relax a bit from studying tough mathematical problems? Read why and how Markus Mohrhard works on LibreOffice!

LibreOffice can only exist since people are working on it: so please ! tell us a bit about yourself.

I’m a third year math student and have always been interested in computer science(which is even a subsidiary subject for me). I’m always interested in anything new in math, physics and computer science and try to learn as much as possible in these areas.

In what other software projects have you been involved ?

I’ve been working on a university project for about one year now. This project is mainly about model to model transformations.

Where do you live (and study)?

I live at Karlsruhe and study at the Karlsruhe Institute for Technology (formerly know as university Karlsruhe)

What do you do when you’re not working on LibreOffice ?

Mainly studying, but in my free time I do sports or just do something with my friends.

Ah sports means healthy people in the project πŸ™‚ …so, what type of sports?

I’m jogging and playing football. But since university I have no more time for doing this in a club only with friends and in my free time.

When do you usually spend time on the project ?

Mainly in the evening and during nights. Mostly when I have some math problems which drive me crazy and I need to think about something else for some time.

Working on LibreOffice code to relax – could be worse πŸ˜‰
Do you have a preferred text editor for this relaxing work? And why?

Notepad++, Vim and Gedit. Depending on what I’m doing. Notepad++ is my prefered editor at Windows and sometimes I miss it in Linux. I think for developing in Linux there is only the choice between Emacs and Vim and I just prefer Vim(even if it sometimes drives me crazy). And I like Gedit for its simplicity.

How did you hear about LibreOffice ?

I’m following a tech news site and they report regularly about Libreoffice and the Documentfoundation. I liked the idea of an independant foundation behind LibreOffice that would not force developers to sign a CLA.

Why did you get involved ?

I’ve always wanted to contribute to an open-source project. After I discovered the Easy Hacks page my decision was made and the community made it really easy to get into the development. Especially Kohei helped me a lot to understand the code around calc.

What was your first contribution to LibreOffice ?

It was a one line change to fix a problem showing the right shortcut. Nothing special but I learned a lot about the structure of LibreOffice there. It was about the crasher bug (fdo#37429) and listed and the most annoying bugs. As soon as I found the problem (which took a lot of time) it was just a one line change.

What was your initial experience of contributing to LibreOffice like ?

It was amazing how positive the core developers react to someone new and how much they encourage someone to go on. Even when I started working on my autofilter patch and made some really bad design decisions, they helped me every time with some hints how I can improve my code.

What have you done since then ?

I’ve written some code to support one autofilter per sheet in calc and the corresponding import and export filters(thanks a lot there for Kohei’s help). Since then I’ve fixed several bugs and started working on supporting an unlimited number of sheets in calc together with improving the performance in some situations.

What do you think was your most important contribution to LibreOffice so far ?

For me it is the support for one autofilter per sheet, but for others it might be one of the bugs I fixed.

How will that improve things for users?

This was a long requested feature and improves the compatibility to Excel a bit. There was a workaround for this this but it was extremely uninitive, so I hope that a lot of people can benefit from this feature.

What is your vision for the future and/or what would you most like to see improved ?

It would be amazing if more people would help in the QA and help the developers to find bugs much earlier. I broke some minor things with my patches but they were not detected before RC1 and I think our quality could improve if there were more people testing the nightly builds or beta builds.

Anything else interesting you get up to when not hacking ?

I’m playing chess and doing sports regularly. But I’m always open to new things and try something different. I’d like to travel to other countries more but that will not possible as long as I study.

Thanks a lot for your answers and time!


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