tklmap v2.2.0 is now available

15 February 2023

This release is almost entirely focused on behind the scenes changes aimed at improving the performance of the site.

New Features

  • Server-side Marker Clustering: the work done to group markers into clusters has been moved entirely to a server-side implementation instead of being done in the browser. This should hopefully improve site performance when zooming in and out of areas with lots of markers. The algorithm used to cluster markers has been recreated to reflect the original Google algorithm as closely as possible, so this shouldn't cause any wild differences in how markers are presented on the map.

  • Marker Caching: marker data fetched from the server is now stored and fetched from an in-memory cache. This will improve the load time of the map when fetching markers, which is important given the change below.

  • Limited Marker View: markers will now only show on the map if they are visible on your screen. As a consequence of this, navigating round the map will show markers popping into existence as your visible area of the map changes.


  • Escape characters should no longer show up in marker infowindows when the 'More Info' field contains a new line. However, newlines are still not showing in marker infowindows, which will be fixed in a future update.

Known Issues

  • When viewing the map, markers may pop out of or be absorbed into a cluster after making minor changes to your view. E.g moving the map slightly left or right may change the clustering landscape despite nothing really changing around that cluster.

  • Clicking clusters at high zoom levels may zoom you in too far to see the markers in question.

Please report any issues you have, especially regarding the above. Weird behaviour with markers on maps, clusters, the map generally misbehaving etc. Any comments regarding the speed of the site would also be appreciated - does it feel faster, slower, or the same?