+## 4.0.0 -> 4.1.0
+
+### ICU tokenizer is the new default
+
+Nominatim now installs the [ICU tokenizer](../customize/Tokenizers.md#icu-tokenizer)
+by default. This only has an effect on newly installed databases. When
+updating older databases, it keeps its installed tokenizer. If you still
+run with the legacy tokenizer, make sure to compile Nominatim with the
+PostgreSQL module, see [Installation](Installation.md#building-nominatim).
+
+### geocodejson output changed
+
+The `type` field of the geocodejson output has changed. It now contains
+the address class of the object instead of the value of the OSM tag. If
+your client has used the `type` field, switch them to read `osm_value`
+instead.
+
+## 3.7.0 -> 4.0.0
+
+### NOMINATIM_PHRASE_CONFIG removed
+
+Custom blacklist configurations for special phrases now need to be handed
+with the `--config` parameter to `nominatim special-phrases`. Alternatively
+you can put your custom configuration in the project directory in a file
+named `phrase-settings.json`.
+
+Version 3.8 also removes the automatic converter for the php format of
+the configuration in older versions. If you are updating from Nominatim < 3.7
+and still work with a custom `phrase-settings.php`, you need to manually
+convert it into a json format.
+
+### PHP utils removed
+
+The old PHP utils have now been removed completely. You need to switch to
+the appropriate functions of the nominatim command line tool. See
+[Introducing `nominatim` command line tool](#introducing-nominatim-command-line-tool)
+below.
+
+## 3.6.0 -> 3.7.0
+
+### New format and name of configuration file
+
+The configuration for an import is now saved in a `.env` file in the project
+directory. This file follows the dotenv format. For more information, see
+the [installation chapter](Import.md#configuration-setup-in-env).
+
+To migrate to the new system, create a new project directory, add the `.env`
+file and port your custom configuration from `settings/local.php`. Most
+settings are named similar and only have received a `NOMINATIM_` prefix.
+Use the default settings in `settings/env.defaults` as a reference.