diff --git a/.github/workflows/build_wheels.yml b/.github/workflows/build_wheels.yml
index 8dc7dc1ba..a397fbc91 100644
--- a/.github/workflows/build_wheels.yml
+++ b/.github/workflows/build_wheels.yml
@@ -10,9 +10,14 @@ on:
           #     default: "v0.4.0"
           upload_to_pypi:
               type: boolean
-              description: Whether the artifacts should be uploaded to PyPI
+              description: Should upload
               required: false
-              default: false
+              default: true
+          test_pypi:
+              type: boolean
+              description: Use Test PyPI
+              required: false
+              default: true
 
 jobs:
   build_wheels:
@@ -71,7 +76,17 @@ jobs:
           path: dist
 
       - uses: pypa/gh-action-pypi-publish@release/v1
+        if: github.event.inputs.test_pypi == 'false'
         with:
           user: __token__
           password: ${{ secrets.PYPI_API_TOKEN }}
           verbose: true
+    
+      - uses: pypa/gh-action-pypi-publish@release/v1
+        if: github.event.inputs.test_pypi == 'true'
+        with:
+          repository-url: https://test.pypi.org/legacy/
+          user: __token__
+          password: ${{ secrets.TESTPYPI_API_TOKEN }}
+          verbose: true
+
diff --git a/pyproject.toml b/pyproject.toml
index 738c6f79c..43e97359d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -48,7 +48,7 @@ before-all = [
     "unzip scip.zip",
     "mv scip_install scip"
     ]
-environment = { SCIPOPTDIR="$(pwd)/scip", LD_LIBRARY_PATH="$(pwd)/scip/lib:$LD_LIBRARY_PATH", DYLD_LIBRARY_PATH="$(pwd)/scip/lib:$DYLD_LIBRARY_PATH", PATH="$(pwd)/scip/bin:$PATH", PKG_CONFIG_PATH="$(pwd)/scip/lib/pkgconfig:$PKG_CONFIG_PATH"}
+environment = { SCIPOPTDIR="$(pwd)/scip", LD_LIBRARY_PATH="$(pwd)/scip/lib:$LD_LIBRARY_PATH", DYLD_LIBRARY_PATH="$(pwd)/scip/lib:$DYLD_LIBRARY_PATH", PATH="$(pwd)/scip/bin:$PATH", PKG_CONFIG_PATH="$(pwd)/scip/lib/pkgconfig:$PKG_CONFIG_PATH", RELEASE="true"}
 
 
 [tool.cibuildwheel.macos]
@@ -64,7 +64,7 @@ fi
 unzip scip.zip
 mv scip_install src/scip
 '''
-environment = {SCIPOPTDIR="$(pwd)/src/scip", LD_LIBRARY_PATH="$(pwd)/src/scip/lib:LD_LIBRARY_PATH", DYLD_LIBRARY_PATH="$(pwd)/src/scip/lib:$DYLD_LIBRARY_PATH", PATH="$(pwd)/src/scip/bin:$PATH", PKG_CONFIG_PATH="$(pwd)/src/scip/lib/pkgconfig:$PKG_CONFIG_PATH"}
+environment = {SCIPOPTDIR="$(pwd)/src/scip", LD_LIBRARY_PATH="$(pwd)/src/scip/lib:LD_LIBRARY_PATH", DYLD_LIBRARY_PATH="$(pwd)/src/scip/lib:$DYLD_LIBRARY_PATH", PATH="$(pwd)/src/scip/bin:$PATH", PKG_CONFIG_PATH="$(pwd)/src/scip/lib/pkgconfig:$PKG_CONFIG_PATH", RELEASE="true"}
 repair-wheel-command = [
   "delocate-listdeps {wheel}",
   "delocate-wheel --require-archs {delocate_archs} -w {dest_dir} {wheel}",
@@ -81,5 +81,5 @@ before-all = [
     "mv .\\test .\\scip"
 ]
 before-build = "pip install delvewheel"
-environment = { SCIPOPTDIR='D:\\a\\PySCIPOpt\\PySCIPOpt\\scip' }
+environment = { SCIPOPTDIR='D:\\a\\PySCIPOpt\\PySCIPOpt\\scip', RELEASE="true" }
 repair-wheel-command = "delvewheel repair --add-path c:/bin;c:/lib;c:/bin/src;c:/lib/src;D:/a/PySCIPOpt/PySCIPOpt/scip/;D:/a/PySCIPOpt/PySCIPOpt/scip/lib/;D:/a/PySCIPOpt/PySCIPOpt/scip/bin/ -w {dest_dir} {wheel}"
diff --git a/setup.py b/setup.py
index 7918c17dd..9424b5749 100644
--- a/setup.py
+++ b/setup.py
@@ -85,7 +85,7 @@
 
 
 on_github_actions = os.getenv('GITHUB_ACTIONS') == 'true'
-release_mode = os.getenv('SCIPOPTSUITE_VERSION') is not None
+release_mode = os.getenv('RELEASE') == 'true'
 compile_with_line_tracing = on_github_actions and not release_mode    
 
 extensions = [
diff --git a/tests/test_model.py b/tests/test_model.py
index d50437417..96e7e51a9 100644
--- a/tests/test_model.py
+++ b/tests/test_model.py
@@ -345,7 +345,7 @@ def test_setLogFile_none():
     os.remove(log_file_name)
    
 def test_locale():
-    on_release = os.getenv('SCIPOPTSUITE_VERSION') is not None
+    on_release = os.getenv('RELEASE') is not None
     if on_release:
         pytest.skip("Skip this test on release builds")