diff --git a/CHANGELOG.md b/CHANGELOG.md
index 58d8f95..821c81e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,46 @@
 # Changelog
 
+## 0.4.0
+
+### Improvements
+
+* Retry OpenID Connect connection if it fails on boot
+* Format log outputs with color and improve access log
+* Make pool_size and overflow configurable for worker and portal
+* Add a route for exporting events as GeoJSON/Shapefile
+* Point footer to forum, not slack (fixes #140)
+* Improve wording on profile page ("My" instead of "Your")
+* Show "My tracks" directly in main menu (fixes #136)
+
+### Bugfixes
+
+* Make sure the API can recover from the broken postgresql connection state
+* Remove duplicate events from the same track
+* Fix direction of road segments (fixes #142)
+* Solve a few problems with the colormap scales in the map view 
+
+### Docs & deployment
+
+* Greatly improve deployement docs for a simple follow-along routine
+* Use environment variables (`OBS_*`) for configuration
+* Fix port numbers in example files and expose 3000 in the image
+* Add `LEAN_MODE` configuration to disable `road` database table usage and fall
+  back to Overpass API for processing tracks (see
+  [docs/lean-mode.md](docs/lean-mode.md)).
+* Read `config.overrides.py` file if it exists
+* Add osm2pgsql to portal image to be able to import OSM data from within the
+  container
+* Fix path to roads_import.lua in docs
+* Explain to use the portal service, instead of api, in production
+* Use entrypoint instead of command, so you can run process_track.py one-off tasks
+
+### Internals
+
+* Use custom `get_single_arg` everywhere, remove sanicargs (fixes #193)
+* Update requirements and make them consistent
+* Fix error handling, especially for file uploads
+ 
+
 ## 0.3.4
 
 ### Features
diff --git a/UPGRADING.md b/UPGRADING.md
index fffcf43..67e9d0c 100644
--- a/UPGRADING.md
+++ b/UPGRADING.md
@@ -5,6 +5,21 @@ Simple migrations, e.g. for adding schema changes, are not documented
 explicitly. Once we implement them, their usage will be described in the
 [README](./README.md).
 
+## 0.4.0
+
+* Rebuild your image, this may take longer than usual, as it will compile
+  `osm2pgsql` for you. Next time, it should be in your docker build cache and
+  be fast again.
+* Add new config flags: `VERBOSE`, `LEAN_MODE`, `POSTGRES_POOL_SIZE`,
+  `POSTGRES_MAX_OVERFLOW`. Check the example config for sane default values.
+* Re-run `tools/prepare_sql_tiles.py` again (see README)
+* It has been made easier to import OSM data, check
+  [deployment/README.md](deployment/README.md) for the sections "Download
+  OpenStreetMap maps" and "Import OpenStreetMap data". You can now download
+  multiple .pbf files and then import them at once, using the docker image
+  built with the `Dockerfile`. Alternatively, you can choose to enable [lean
+  mode](docs/lean-mode.md). You do not need to reimport data, but setting this
+  up now will make your life easier in the long run ;)
 
 ## v0.2 to v0.3 (MongoDB to PostgreSQL)