Hi, thanks for stopping by! My name is Martijn van Exel. I have been contributing to OSM as a mapper, community organizer and developer since 2007. I was on the OSMF board between 2015 and 2018 and on the OSM US board between 2012 and 2021. I created MapRoulette, the open source micro-tasking tool, and maintain some smaller OSM-related open source software projects. I run OpenStreetMap Utah. We hold monthly events where local mappers meet up. I have presented at many OSM conferences on a variety of topics. YouTube has some recordings.

I have been involved with OpenStreetMap in a professional capacity before: at Telenav (2011-2018) where I helped transition our map data backend to 100% OSM, then at TomTom (2018-2021) where I was part of a small R&D team and at HERE Technologies (2021-2022) where I was involved in open data product strategy. My current job does not involve OpenStreetMap in any significant way.

You can message me here or in the OSM US Slack. If you happen to be in the Salt Lake City area, please drop me a line, I love to meet OSMers from everywhere!

I am on Mastodon.

Current mapping interests

Cleaning up after old imports, particularly TIGER, is an enduring pastime. Pedestrian and bike infrastructure. POIs (shops and other businesses). Mobile mapping (GoMap!!).

Other OSM things I currently work on

Organizing meetups! Making sure MapRoulette and the other OSM US Charter Projects keep going in a good direction.

Software

• changesets-to-parquet takes an OSM changeset dump file from planet.osm.org and converts it into a parquet file.
• Meet Your Mappers is a website that lets you find active mappers near you.
• osmdiff is an unfortunately poorly maintained python library to interact with OSM diff / augmented diff objects.
• OSM Tools Extension is a Firefox / Chrome extension that gives you quick access to OSM related map websites. There’s other tools that do similar things but this one is real lightweight and easy to extend.
• OSM Then and Now lets you create tile sets from old OSM planet files and serve them as a side-by-side map
• Overpass Python API a Python interface to do overpass queries.

My contributions to OSM in any form are on personal title unless otherwise stated.