diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 203e752..02c1b3b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -23,4 +23,4 @@ jobs:
       - name: Lint
         run: uvx ruff check .
       - name: Type check
-        run: uvx --with . pyright .
+        run: uvx --with ".[dev]" pyright .
diff --git a/pyproject.toml b/pyproject.toml
index fca4aff..d9acfcd 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -28,6 +28,7 @@ kaleido = "kaleido_cli.app:main"
 dev = [
     "pytest>=8.0.0",
     "pytest-asyncio>=0.23.0",
+    "pytest-mock>=3.15.1",
 ]
 
 [project.urls]
diff --git a/uv.lock b/uv.lock
index f3d4e57..80270a8 100644
--- a/uv.lock
+++ b/uv.lock
@@ -178,6 +178,7 @@ dependencies = [
 dev = [
     { name = "pytest" },
     { name = "pytest-asyncio" },
+    { name = "pytest-mock" },
 ]
 
 [package.dev-dependencies]
@@ -192,6 +193,7 @@ requires-dist = [
     { name = "kaleido-sdk", specifier = "==0.1.5" },
     { name = "pytest", marker = "extra == 'dev'", specifier = ">=8.0.0" },
     { name = "pytest-asyncio", marker = "extra == 'dev'", specifier = ">=0.23.0" },
+    { name = "pytest-mock", marker = "extra == 'dev'", specifier = ">=3.15.1" },
     { name = "pyyaml", specifier = ">=6.0.0" },
     { name = "rich", specifier = ">=13.0.0" },
     { name = "shellingham", specifier = ">=1.5" },