diff --git a/.github/workflows/unit_tests.yml b/.github/workflows/unit_tests.yml
index f2b6291c7..c5013e5e8 100644
--- a/.github/workflows/unit_tests.yml
+++ b/.github/workflows/unit_tests.yml
@@ -143,7 +143,7 @@ jobs:
     - name: Install MNE (stable)
       if: "matrix.os != 'ubuntu-latest'"
       run: |
-        git clone --depth 1 https://github.com/mne-tools/mne-python.git -b main  # XXX: move to maint/0.24 after release
+        git clone --depth 1 https://github.com/mne-tools/mne-python.git -b maint/0.24
         pip install --no-deps -e ./mne-python
 
     - name: Install MNE (main)
diff --git a/doc/conf.py b/doc/conf.py
index 7fcea671f..2ed2bab62 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -140,8 +140,9 @@
 
 html_context = {
     'versions_dropdown': {
-        'dev': 'v0.9 (devel)',
-        'stable': 'v0.8 (stable)',
+        'dev': 'v0.10 (devel)',
+        'stable': 'v0.9 (stable)',
+        'v0.8': 'v0.8',
         'v0.7': 'v0.7',
         'v0.6': 'v0.6',
         'v0.5': 'v0.5',
diff --git a/doc/whats_new.rst b/doc/whats_new.rst
index cc1a62db0..85ccba8ce 100644
--- a/doc/whats_new.rst
+++ b/doc/whats_new.rst
@@ -9,25 +9,41 @@ What's new?
 
 .. _changes_0_9:
 
-Version 0.9 (unreleased)
+Version 0.9 (2021-11-23)
 ------------------------
 
-...
+This release brings compatibility with MNE-Python 0.24 and some new convenience
+functions and speedups of existing code to help you be more productive! 👩🏽‍💻
+And, of course, plenty of bug fixes. 🐞
 
 Notable changes
 ~~~~~~~~~~~~~~~
 
-- ...
+- 🧠 Compatibility with MNE-Python 0.24!
+- 👻 Anonymize an entire BIDS dataset via :func:`mne_bids.anonymize_dataset`!
+- 🏝 Conveniently turn a path into a :class:`BIDSPath` via
+  :func:`get_bids_path_from_fname`!
+- 🏎 :func:`mne_bids.stats.count_events` and :meth:`mne_bids.BIDSPath.match`
+  are operating **much** faster now!
+- 🔍 :func:`write_raw_bids` now stores the names of the input files in the
+  ``source`` column of ``*_scans.tsv``, making it easier for you to
+  *go back to the source* should you ever need to!
 
 Authors
 ~~~~~~~
 
+People who contributed to this release (in alphabetical order):
+
+* `Adam Li`_
 * `Alex Rockhill`_
-* `Richard Höchenberger`_
+* `Alexandre Gramfort`_
+* `Clemens Brunner`_
+* `Franziska von Albedyll`_
+* `Julia Guiomar Niso Galán`_
 * `Mainak Jas`_
-* `Adam Li`_
+* `Marijn van Vliet`_
+* `Richard Höchenberger`_
 * `Stefan Appelhoff`_
-* `Franziska von Albedyll`_
 
 Detailed list of changes
 ~~~~~~~~~~~~~~~~~~~~~~~~
@@ -66,7 +82,7 @@ API and behavior changes
 
 - :func:`mne_bids.get_entities_from_fname` does not return ``suffix`` anymore as that is not considered a BIDS entity, by `Adam Li`_ (:gh:`883`)
 
-- Reading BIDS data with ``"HeadCoilFrequency"`` and ``"PowerLineFrequency"`` data specified in JSON sidecars will only "warn" in case of mismatches between Raw and JSON data, by `Franziska von Albedyll`_ (:gh:`885`)
+- Reading BIDS data with ``"HeadCoilFrequency"`` and ``"PowerLineFrequency"`` data specified in JSON sidecars will only "warn" in case of mismatches between Raw and JSON data, by `Franziska von Albedyll`_ (:gh:`855`)
 
 - Accessing :attr:`mne_bids.BIDSPath.fpath` emit a warning anymore if the path does not exist. This behavior was unreliable and yielded confusing error messages in certain use cases. Use `mne_bids.BIDSPath.fpath.exists()` to check whether the path exists in the file system, by `Richard Höchenberger`_ (:gh:`904`)
 
@@ -83,7 +99,6 @@ Requirements
 
 - Writing BrainVision files now requires ``pybv`` version 0.6, by `Stefan Appelhoff`_ (:gh:`880`)
 
-
 Bug fixes
 ^^^^^^^^^
 
diff --git a/mne_bids/__init__.py b/mne_bids/__init__.py
index 863368ab2..08ade83a8 100644
--- a/mne_bids/__init__.py
+++ b/mne_bids/__init__.py
@@ -1,6 +1,6 @@
 """MNE software for easily interacting with BIDS compatible datasets."""
 
-__version__ = '0.9.dev0'
+__version__ = '0.9'
 from mne_bids import commands
 from mne_bids.report import make_report
 from mne_bids.path import (BIDSPath, get_datatypes, get_entity_vals,
diff --git a/mne_bids/write.py b/mne_bids/write.py
index d730bddea..943812986 100644
--- a/mne_bids/write.py
+++ b/mne_bids/write.py
@@ -437,8 +437,7 @@ def _scans_tsv(raw, raw_fname, fname, keep_source, overwrite=False):
     fname : str
         Filename to save the scans.tsv to.
     keep_source : bool
-        If ``True`` (default), ``raw.filenames`` will
-        be stored in the ``source`` column.
+        Wehter to store``raw.filenames`` in the ``source`` column.
     overwrite : bool
         Defaults to False.
         Whether to overwrite the existing data in the file.
@@ -1179,12 +1178,13 @@ def write_raw_bids(raw, bids_path, events_data=None, event_id=None,
 
         ``keep_his`` : bool
             If ``False`` (default), all subject information next to the
-            recording date will be overwritten as well. If True, keep subject
-            information apart from the recording date.
+            recording date will be overwritten as well. If ``True``, keep
+            subject information apart from the recording date.
 
         ``keep_source`` : bool
-            If ``True`` (default), the filename of the raw source will
-            be stored in the ``source`` column of  ``scans.tsv``.
+            Whether to store the name of the ``raw`` input file in the
+            ``source`` column of ``scans.tsv``. By default, this information
+            is not stored.
 
     format : 'auto' | 'BrainVision' | 'EDF' | 'FIF'
         Controls the file format of the data after BIDS conversion. If