diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 11e2cfbc..9b0fe651 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -107,6 +107,44 @@ jobs:
           pip install -vv -e .
           SKIP_BZIP_TEST=true pytest -vv fitsio
 
+      - name: test install sdist .gz with no unit tests
+        shell: bash -l {0}
+        run: |
+          rm -rf build*
+          rm -rf $HOME/cfitsio-static-install
+          find . -name "*.so" -type f -delete
+          rm -rf dist
+
+          python setup.py sdist
+
+          pip install -vv --no-deps --no-build-isolation dist/*.tar.gz
+          cd ..
+          python -c "import fitsio; assert fitsio.__version__ != '0.0.0'"
+          cd -
+          pip uninstall fitsio --yes
+
+      - name: test sdist
+        shell: bash -l {0}
+        run: |
+          rm -rf build*
+          rm -rf $HOME/cfitsio-static-install
+          find . -name "*.so" -type f -delete
+          rm -rf dist
+
+          python setup.py sdist
+          pushd dist/
+
+          fname=$(ls fitsio*.gz)
+          tar xvfz "$fname"
+          dname=$(echo "$fname" | sed 's/\.tar\.gz//')
+          pushd $dname
+
+          pip install -vv -e .
+          SKIP_BZIP_TEST=true pytest -vv fitsio
+
+          popd
+          popd
+
       - name: flake8
         shell: bash -l {0}
         run: |
diff --git a/CHANGES.md b/CHANGES.md
index 103586f0..31c87e37 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,14 +1,16 @@
-version 1.2.3 (not yet released)
+version 1.2.3
 -------------
 
 Changes
 
     - bundle cfitsio 4.4.0.
+    - update manifest to include new cfitsio
 
 Bug Fixes
 
     - Reading images with empty slices was returning data
     - Using cfitsio 4.4.0 fixes a bug reading HIERARCH+CONTINUE keywords
+    - zlib subdir not in manifest
 
 version 1.2.2
 -------------
diff --git a/MANIFEST.in b/MANIFEST.in
index caab1fcb..51e80e45 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1,5 +1,6 @@
 include *.txt
 include README.md
-recursive-include cfitsio-4.2.0 *
+recursive-include cfitsio-4.4.0 *
 recursive-include patches *
 recursive-include fitsio/test_images *
+recursive-include zlib *