diff --git a/src/pip_deepfreeze/__main__.py b/src/pip_deepfreeze/__main__.py
index 88cfd9e..05fda1b 100644
--- a/src/pip_deepfreeze/__main__.py
+++ b/src/pip_deepfreeze/__main__.py
@@ -7,7 +7,7 @@
 from packaging.utils import canonicalize_name
 from packaging.version import Version
 
-from .pip import InstallerFlavor
+from .pip import Installer, InstallerFlavor
 from .pyproject_toml import load_pyproject_toml
 from .sanity import check_env
 from .sync import sync as sync_operation
@@ -91,6 +91,7 @@ def sync(
     constraints. Optionally uninstall unneeded dependencies.
     """
     sync_operation(
+        Installer.create(flavor=installer, python=ctx.obj.python),
         ctx.obj.python,
         upgrade_all,
         comma_split(to_upgrade),
@@ -99,7 +100,6 @@ def sync(
         project_root=ctx.obj.project_root,
         pre_sync_commands=pre_sync_commands,
         post_sync_commands=post_sync_commands,
-        installer_flavor=installer,
     )
 
 
diff --git a/src/pip_deepfreeze/pip.py b/src/pip_deepfreeze/pip.py
index 839430b..871c9b2 100644
--- a/src/pip_deepfreeze/pip.py
+++ b/src/pip_deepfreeze/pip.py
@@ -92,11 +92,11 @@ def uninstall_cmd(self, python: str) -> List[str]:
 
 
 def pip_upgrade_project(
+    installer: Installer,
     python: str,
     constraints_filename: Path,
     project_root: Path,
     extras: Optional[Sequence[NormalizedName]] = None,
-    installer: Installer | None = None,
     installer_options: Optional[List[str]] = None,
 ) -> None:
     """Upgrade a project.
@@ -125,8 +125,6 @@ def pip_upgrade_project(
     update the version specifier in requirements.txt, and reinstalling the project with
     this function.
     """
-    if installer is None:
-        installer = PipInstaller()
     constraints_without_editables_filename = get_temp_path_in_dir(
         dir=project_root, prefix="requirements.", suffix=".txt.df"
     )
diff --git a/src/pip_deepfreeze/sync.py b/src/pip_deepfreeze/sync.py
index 03c3001..4a774ed 100644
--- a/src/pip_deepfreeze/sync.py
+++ b/src/pip_deepfreeze/sync.py
@@ -6,7 +6,6 @@
 
 from .pip import (
     Installer,
-    InstallerFlavor,
     pip_fixup_vcs_direct_urls,
     pip_freeze_dependencies_by_extra,
     pip_uninstall,
@@ -54,6 +53,7 @@ def _constraints_path(project_root: Path) -> Path:
 
 
 def sync(
+    installer: Installer,
     python: str,
     upgrade_all: bool,
     to_upgrade: List[str],
@@ -62,9 +62,7 @@ def sync(
     project_root: Path,
     pre_sync_commands: Sequence[str] = (),
     post_sync_commands: Sequence[str] = (),
-    installer_flavor: InstallerFlavor = InstallerFlavor.pip,
 ) -> None:
-    installer = Installer.create(installer_flavor, python)
     # run pre-sync commands
     run_commands(pre_sync_commands, project_root, "pre-sync")
     # sync
@@ -88,11 +86,11 @@ def sync(
             else:
                 print(req_line.raw_line, file=constraints)
     pip_upgrade_project(
+        installer,
         python,
         merged_constraints_path,
         project_root,
         extras=extras,
-        installer=installer,
         installer_options=installer_options,
     )
     # freeze dependencies
diff --git a/tests/test_pip.py b/tests/test_pip.py
index ed4e95a..a1d0fa6 100644
--- a/tests/test_pip.py
+++ b/tests/test_pip.py
@@ -6,6 +6,9 @@
 from packaging.requirements import Requirement
 
 from pip_deepfreeze.pip import (
+    Installer,
+    PipInstaller,
+    UvpipInstaller,
     _pip_list__env_info_json,
     _pip_list__pip_inspect,
     pip_freeze,
@@ -174,21 +177,26 @@ def test_pip_freeze_dependencies_by_extra(
         ([], [], []),
     ],
 )
-def test_pip_uninstall(to_install, to_uninstall, expected, virtualenv_python, testpkgs):
+@pytest.mark.parametrize("installer", [PipInstaller(), UvpipInstaller()])
+def test_pip_uninstall(
+    to_install,
+    to_uninstall,
+    expected,
+    installer: Installer,
+    virtualenv_python,
+    testpkgs,
+):
     if to_install:
         subprocess.call(
             [
-                virtualenv_python,
-                "-m",
-                "pip",
-                "install",
+                *installer.install_cmd(virtualenv_python),
                 "--no-index",
                 "--find-links",
                 testpkgs,
                 *to_install,
             ]
         )
-    pip_uninstall(virtualenv_python, to_uninstall)
+    pip_uninstall(installer, virtualenv_python, to_uninstall)
     assert list(_freeze_filter(pip_freeze(virtualenv_python))) == expected
 
 
@@ -201,7 +209,10 @@ def _freeze_filter(reqs: Iterable[str]) -> Iterator[str]:
         yield req
 
 
-def test_pip_upgrade_project(virtualenv_python, testpkgs, tmp_path):
+@pytest.mark.parametrize("installer", [PipInstaller(), UvpipInstaller()])
+def test_pip_upgrade_project(
+    installer: Installer, virtualenv_python, testpkgs, tmp_path
+):
     constraints = tmp_path / "requirements.txt.df"
     # First install, pkgc frozen to 0.0.1.
     (tmp_path / "setup.py").write_text(
@@ -217,15 +228,21 @@ def test_pip_upgrade_project(virtualenv_python, testpkgs, tmp_path):
         )
     )
     constraints.write_text(f"--no-index\n--find-links {testpkgs}\npkgc==0.0.1")
-    pip_upgrade_project(virtualenv_python, constraints, project_root=tmp_path)
+    pip_upgrade_project(
+        installer, virtualenv_python, constraints, project_root=tmp_path
+    )
     assert list(_freeze_filter(pip_freeze(virtualenv_python))) == ["pkgc==0.0.1"]
     # Upgrade pkgc by adding a different constraint.
     constraints.write_text(f"--no-index\n--find-links {testpkgs}\npkgc<=0.0.2")
-    pip_upgrade_project(virtualenv_python, constraints, project_root=tmp_path)
+    pip_upgrade_project(
+        installer, virtualenv_python, constraints, project_root=tmp_path
+    )
     assert list(_freeze_filter(pip_freeze(virtualenv_python))) == ["pkgc==0.0.2"]
     # Upgrade pkgc to latest version by removing it from constraints.
     constraints.write_text(f"--no-index\n--find-links {testpkgs}")
-    pip_upgrade_project(virtualenv_python, constraints, project_root=tmp_path)
+    pip_upgrade_project(
+        installer, virtualenv_python, constraints, project_root=tmp_path
+    )
     assert list(_freeze_filter(pip_freeze(virtualenv_python))) == ["pkgc==0.0.3"]
     # Remove dependency from setup.py but it is still in frozen requirements,
     # the upgrade procedure does not remove it.
@@ -242,16 +259,23 @@ def test_pip_upgrade_project(virtualenv_python, testpkgs, tmp_path):
         )
     )
     constraints.write_text(f"--no-index\n--find-links {testpkgs}\npkgc==0.0.3")
-    pip_upgrade_project(virtualenv_python, constraints, project_root=tmp_path)
+    pip_upgrade_project(
+        installer, virtualenv_python, constraints, project_root=tmp_path
+    )
     assert list(_freeze_filter(pip_freeze(virtualenv_python))) == ["pkgc==0.0.3"]
     # Remove dependency from frozen requirements, check the upgrade procedure
     # does not remove it (it is now an unrelated package which we leave alone).
     constraints.write_text(f"--no-index\n--find-links {testpkgs}")
-    pip_upgrade_project(virtualenv_python, constraints, project_root=tmp_path)
+    pip_upgrade_project(
+        installer, virtualenv_python, constraints, project_root=tmp_path
+    )
     assert list(_freeze_filter(pip_freeze(virtualenv_python))) == ["pkgc==0.0.3"]
 
 
-def test_pip_upgrade_constraint_not_a_dep(virtualenv_python, testpkgs, tmp_path):
+@pytest.mark.parametrize("installer", [PipInstaller(), UvpipInstaller()])
+def test_pip_upgrade_constraint_not_a_dep(
+    installer: Installer, virtualenv_python, testpkgs, tmp_path
+):
     """Test upgrading does not install constraints that are not dependencies."""
     constraints = tmp_path / "requirements.txt.df"
     # First install, pkgc frozen to 0.0.1.
@@ -265,11 +289,16 @@ def test_pip_upgrade_constraint_not_a_dep(virtualenv_python, testpkgs, tmp_path)
         )
     )
     constraints.write_text(f"--no-index\n--find-links {testpkgs}\npkgc==0.0.1")
-    pip_upgrade_project(virtualenv_python, constraints, project_root=tmp_path)
+    pip_upgrade_project(
+        installer, virtualenv_python, constraints, project_root=tmp_path
+    )
     assert list(_freeze_filter(pip_freeze(virtualenv_python))) == []
 
 
-def test_pip_upgrade_vcs_url(virtualenv_python, tmp_path, capfd):
+@pytest.mark.parametrize("installer", [PipInstaller(), UvpipInstaller()])
+def test_pip_upgrade_vcs_url(
+    installer: Installer, virtualenv_python, testpkgs, tmp_path, capfd
+):
     """Test upgrading a VCS URL."""
     constraints = tmp_path / "requirements.txt.df"
     (tmp_path / "setup.py").write_text(
@@ -285,8 +314,14 @@ def test_pip_upgrade_vcs_url(virtualenv_python, tmp_path, capfd):
         )
     )
     # install tag 0.10.0
-    constraints.write_text("--no-index\ntoml @ git+https://github.com/uiri/toml@0.10.0")
-    pip_upgrade_project(virtualenv_python, constraints, project_root=tmp_path)
+    constraints.write_text(
+        "--no-index\n"
+        f"--find-links {testpkgs}\n"
+        "toml @ git+https://github.com/uiri/toml@0.10.0"
+    )
+    pip_upgrade_project(
+        installer, virtualenv_python, constraints, project_root=tmp_path
+    )
     assert list(_freeze_filter(pip_freeze(virtualenv_python))) == [
         "toml @ git+https://github.com/uiri/toml"
         "@4935f616ef78c35a968b2473e806d7049eba9af1"
@@ -295,17 +330,26 @@ def test_pip_upgrade_vcs_url(virtualenv_python, tmp_path, capfd):
     # reinstall, no change but different @url syntax
     constraints.write_text(
         "--no-index\n"
+        f"--find-links {testpkgs}\n"
         "toml@git+https://github.com/uiri/toml@4935f616ef78c35a968b2473e806d7049eba9af1"
     )
-    pip_upgrade_project(virtualenv_python, constraints, project_root=tmp_path)
+    pip_upgrade_project(
+        installer, virtualenv_python, constraints, project_root=tmp_path
+    )
     assert list(_freeze_filter(pip_freeze(virtualenv_python))) == [
         "toml @ git+https://github.com/uiri/toml"
         "@4935f616ef78c35a968b2473e806d7049eba9af1"
     ]
     assert "Uninstalling dependencies to update" not in capfd.readouterr().err
     # upgrade to tag 0.10.1
-    constraints.write_text("toml @ git+https://github.com/uiri/toml@0.10.1")
-    pip_upgrade_project(virtualenv_python, constraints, project_root=tmp_path)
+    constraints.write_text(
+        "--no-index\n"
+        f"--find-links {testpkgs}\n"
+        "toml @ git+https://github.com/uiri/toml@0.10.1"
+    )
+    pip_upgrade_project(
+        installer, virtualenv_python, constraints, project_root=tmp_path
+    )
     assert list(_freeze_filter(pip_freeze(virtualenv_python))) == [
         "toml @ git+https://github.com/uiri/toml"
         "@a86fc1fbd650a19eba313c3f642c9e2c679dc8d6"
diff --git a/tests/test_sync.py b/tests/test_sync.py
index 3c7ec70..7a5fe30 100644
--- a/tests/test_sync.py
+++ b/tests/test_sync.py
@@ -6,7 +6,13 @@
 from typer.testing import CliRunner
 
 from pip_deepfreeze.__main__ import app
-from pip_deepfreeze.pip import pip_freeze, pip_list
+from pip_deepfreeze.pip import (
+    Installer,
+    PipInstaller,
+    UvpipInstaller,
+    pip_freeze,
+    pip_list,
+)
 from pip_deepfreeze.sync import sync
 
 
@@ -134,8 +140,12 @@ def test_editable_default_install(virtualenv_python, editable_foobar_path):
     assert "-e " in "\n".join(pip_freeze(virtualenv_python))
 
 
-def test_sync_project_root(virtualenv_python, editable_foobar_path):
+@pytest.mark.parametrize("installer", [PipInstaller(), UvpipInstaller()])
+def test_sync_project_root(
+    installer: Installer, virtualenv_python, editable_foobar_path
+):
     sync(
+        installer,
         virtualenv_python,
         upgrade_all=False,
         to_upgrade=[],
@@ -177,7 +187,8 @@ def test_sync_editable_dep(virtualenv_python, tmp_path):
     assert "-e " in requirements_path.read_text(), requirements_path.read_text()
 
 
-def test_sync_uninstall(virtualenv_python, tmp_path, testpkgs):
+@pytest.mark.parametrize("installer", [PipInstaller(), UvpipInstaller()])
+def test_sync_uninstall(installer: Installer, virtualenv_python, tmp_path, testpkgs):
     setup_py = tmp_path / "setup.py"
     setup_py.write_text(
         textwrap.dedent(
@@ -192,6 +203,7 @@ def test_sync_uninstall(virtualenv_python, tmp_path, testpkgs):
     in_reqs = tmp_path / "constraints.txt"
     in_reqs.write_text(f"--no-index\n-f {testpkgs}")
     sync(
+        installer,
         virtualenv_python,
         upgrade_all=False,
         to_upgrade=[],
@@ -212,6 +224,7 @@ def test_sync_uninstall(virtualenv_python, tmp_path, testpkgs):
     )
     # sync with uninstall=False, pkga remains
     sync(
+        installer,
         virtualenv_python,
         upgrade_all=False,
         to_upgrade=[],
@@ -222,6 +235,7 @@ def test_sync_uninstall(virtualenv_python, tmp_path, testpkgs):
     assert "pkga==" in "\n".join(pip_freeze(virtualenv_python))
     # sync with uninstall=True, pkga removed
     sync(
+        installer,
         virtualenv_python,
         upgrade_all=False,
         to_upgrade=[],
@@ -233,7 +247,10 @@ def test_sync_uninstall(virtualenv_python, tmp_path, testpkgs):
 
 
 @pytest.mark.xfail(reason="https://github.com/sbidoul/pip-deepfreeze/issues/24")
-def test_sync_update_new_dep(virtualenv_python, testpkgs, tmp_path):
+@pytest.mark.parametrize("installer", [PipInstaller(), UvpipInstaller()])
+def test_sync_update_new_dep(
+    installer: Installer, virtualenv_python, testpkgs, tmp_path
+):
     """Test that a preinstalled dependency is updated when project is not installed
     before sync.
 
@@ -241,10 +258,7 @@ def test_sync_update_new_dep(virtualenv_python, testpkgs, tmp_path):
     """
     subprocess.check_call(
         [
-            virtualenv_python,
-            "-m",
-            "pip",
-            "install",
+            *installer.install_cmd(virtualenv_python),
             "--no-index",
             "-f",
             testpkgs,
@@ -270,6 +284,7 @@ def test_sync_update_new_dep(virtualenv_python, testpkgs, tmp_path):
         )
     )
     sync(
+        installer,
         virtualenv_python,
         upgrade_all=False,
         to_upgrade=["pkgc"],
@@ -281,7 +296,10 @@ def test_sync_update_new_dep(virtualenv_python, testpkgs, tmp_path):
 
 
 @pytest.mark.xfail(reason="https://github.com/sbidoul/pip-deepfreeze/issues/24")
-def test_sync_update_all_new_dep(virtualenv_python, testpkgs, tmp_path):
+@pytest.mark.parametrize("installer", [PipInstaller(), UvpipInstaller()])
+def test_sync_update_all_new_dep(
+    installer: Installer, virtualenv_python, testpkgs, tmp_path
+):
     """Test that a preinstalled dependency is updated when project is not installed
     before sync.
 
@@ -289,10 +307,7 @@ def test_sync_update_all_new_dep(virtualenv_python, testpkgs, tmp_path):
     """
     subprocess.check_call(
         [
-            virtualenv_python,
-            "-m",
-            "pip",
-            "install",
+            *installer.install_cmd(virtualenv_python),
             "--no-index",
             "-f",
             testpkgs,
@@ -318,6 +333,7 @@ def test_sync_update_all_new_dep(virtualenv_python, testpkgs, tmp_path):
         )
     )
     sync(
+        installer,
         virtualenv_python,
         upgrade_all=True,
         to_upgrade=[],
@@ -328,7 +344,8 @@ def test_sync_update_all_new_dep(virtualenv_python, testpkgs, tmp_path):
     assert "pkgc==0.0.3" in "\n".join(pip_freeze(virtualenv_python))
 
 
-def test_sync_extras(virtualenv_python, testpkgs, tmp_path):
+@pytest.mark.parametrize("installer", [PipInstaller(), UvpipInstaller()])
+def test_sync_extras(installer: Installer, virtualenv_python, testpkgs, tmp_path):
     (tmp_path / "setup.py").write_text(
         textwrap.dedent(
             """\
@@ -353,6 +370,7 @@ def test_sync_extras(virtualenv_python, testpkgs, tmp_path):
         )
     )
     sync(
+        installer,
         virtualenv_python,
         upgrade_all=False,
         to_upgrade=[],
@@ -371,6 +389,7 @@ def test_sync_extras(virtualenv_python, testpkgs, tmp_path):
     # now sync again with a different frozen extra dependency
     (tmp_path / "requirements-c.txt").write_text("pkgc==0.0.2")
     sync(
+        installer,
         virtualenv_python,
         upgrade_all=False,
         to_upgrade=[],