, a Mastodon instance for the mapping and geospatial community

Since Elon Musk’s chaotic takeover of Twitter, between contested choices, massive layoffs and misjudgments, a growing number of its users are fleeing the network. Some have closed their account for good, others are deactivating it, and others (like me) are slowing down their activity. The opportunity makes the thief: the toxic side of Twitter has been taking precedence for some time over its most rewarding aspects. For many, fueled by a lot of great conversations, we stayed on it by dodging its most painful aspects: the opacity of the algorithm that decides for us what content we access, the permanent incitement to conflict by design (engagement, they said), traffic analysis via the URL shortener, etc.

There was clearly a need for a new home to continue the conversation.

Introducing Mastodon

A free, decentralized and interoperable alternative to Twitter has been around since 2016, Mastodon.

  • Free: Mastodon’s source code is published on Github under the AGPLv3+ license.
  • Decentralized: Unlike Twitter, Mastodon does not depend on a single service provider. It takes the form of a set of instances (or servers), administered separately but which communicate together in a simple and transparent way. This aspect requires some time to adapt when you come from a centralized web and a platform like Twitter. The analogy with e-mail (we all exchange e-mails but are registered with different providers) can make it easier to understand at first.
  • Interoperable: Mastodon is based on ActivityPub, an open, interoperable and documented standard exchange format. It is implemented by a set of software and services - Peertube (video hosting and viewing) or Pixelfed (free alternative to Instagram) among the most famous. The ongoing migration of Twitter users to Mastodon seems to have revived interest in ActivityPub, while Tumblr has indicated that it will soon integrate the standard.

If you’re looking for the how-to, this introduction to Mastodon is a good place to start.

Beyond the technical aspect of the exchange protocol that it shares with other tools, Mastodon is part of the vast Fediverse movement, a federation of free and open services thought and designed as an alternative to closed and commercial social networks. The Fediverse is a very nice Pandora’s box with several doors of entry - I invite you to push the one to discover more.


Enthused by Mastodon, I had created a first account some time ago, replaced in spring 2020 (during the first lockdown) by a second one on, a server made available by the association la Quadrature du Net. At the end of October, activity suddenly intensified on Mastodon, while on Twitter, a recurring question came up: “on which instance should I register?” - because the multiplication of servers, despite directories like the one proposed by, did not seem to facilitate adoption.

How could I encourage, at my level, this happy migration to the Fediverse and Mastodon?

I chose to pass to the admin side by making available a server specially designed for the community of cartographers, geospatial developers and other map lovers. opened its doors on November 5th, supported by a pun that was hard to pass up, and a series of emojis all more cartos than the others -QGIS, COG, ArcGIS, GDAL, Google Earth, GRASS GIS, you name it- the list continues to grow!

As of November 28, Mapstodon has reached almost 900 subscribers, and the exchanges are getting bigger every day. It’s a pleasure to see this community come to birth and growing, composed of Mastodon regulars and newcomers. As soon as I announced the creation of the forum, three people offered to help me with moderation - thanks to David, Darrell and Joshua.

See you in a few weeks or months for a more complete review. In the meantime, if you’re obsessed with maps or geographic data, we look forward to seeing you at!

Jérémy Garniaux
Jérémy Garniaux
Cartographer & developer