diff --git a/README.md b/README.md
index 26b25aa..866440f 100644
--- a/README.md
+++ b/README.md
@@ -148,7 +148,7 @@ Creates a Python application using the Python interpreter specified based on the
 - **python**: The Python interpreter to use (_default:_ `pkgs.python3`).
 - **preferWheels** : Use wheels rather than sdist as much as possible (_default_: `false`).
 - **groups**: Which Poetry 1.2.0+ dependency groups to install (_default_: `[ ]`).
-- **checkGroups**: Which Poetry 1.2.0+ dependency groups to run unit tests (_default_: `[  "dev" ]`).
+- **checkGroups**: Which Poetry 1.2.0+ dependency groups to install (independently of **groups**) to run unit tests (_default_: `[ "dev" ]`).
 - **extras**: Which Poetry `extras` to install (_default_: `[ "*" ]`, all extras).
 
 Other attributes are passed through to `buildPythonApplication`.
@@ -206,7 +206,7 @@ Creates an environment that provides a Python interpreter along with all depende
 - **extraPackages**: A function taking a Python package set and returning a list of extra packages to include in the environment. This is intended for packages deliberately not added to `pyproject.toml` that you still want to include. An example of such a package may be `pip`. (_default:_ `(ps: [ ])`).
 - **preferWheels** : Use wheels rather than sdist as much as possible (_default_: `false`).
 - **groups**: Which Poetry 1.2.0+ dependency groups to install (_default_: `[ "dev" ]`).
-- **checkGroups**: Which Poetry 1.2.0+ dependency groups to run unit tests (_default_: `[  "dev" ]`).
+- **checkGroups**: Which Poetry 1.2.0+ dependency groups to install (independently of **groups**) to run unit tests (_default_: `[ "dev" ]`).
 - **extras**: Which Poetry `extras` to install (_default_: `[ "*" ]`, all extras).
 
 #### Example
@@ -278,7 +278,7 @@ Creates an attribute set of the shape `{ python, poetryPackages, pyProject, poet
 - **editablePackageSources**: A mapping from package name to source directory, these will be installed in editable mode (_default:_ `{}`).
 - **preferWheels** : Use wheels rather than sdist as much as possible (_default_: `false`).
 - **groups**: Which Poetry 1.2.0+ dependency groups to install (_default_: `[ ]`).
-- **checkGroups**: Which Poetry 1.2.0+ dependency groups to run unit tests (_default_: `[  "dev" ]`).
+- **checkGroups**: Which Poetry 1.2.0+ dependency groups to install (independently of **groups**) to run unit tests (_default_: `[ "dev" ]`).
 - **extras**: Which Poetry `extras` to install (_default_: `[ "*" ]`, all extras).
 
 #### Example
diff --git a/default.nix b/default.nix
index 16ad4b6..0fb9c83 100644
--- a/default.nix
+++ b/default.nix
@@ -24,13 +24,15 @@ let
   knownBuildSystems = lib.importJSON ./known-build-systems.json;
   nixpkgsBuildSystems = lib.subtractLists [ "poetry" "poetry-core" ] knownBuildSystems;
 
+  checkGroupsDefault = [ "dev" ];
+
   mkInputAttrs =
     { py
     , pyProject
     , attrs
     , includeBuildSystem ? true
     , groups ? [ ]
-    , checkGroups ? [ "dev" ]
+    , checkGroups ? checkGroupsDefault
     , extras ? [ "*" ]  # * means all extras, otherwise include the dependencies for a given extra
     }:
     let
@@ -144,7 +146,7 @@ lib.makeScope pkgs.newScope (self: {
     , editablePackageSources ? { }
     , pyProject ? readTOML pyproject
     , groups ? [ ]
-    , checkGroups ? [ "dev" ]
+    , checkGroups ? checkGroupsDefault
     , extras ? [ "*" ]
     }:
     let
@@ -311,7 +313,7 @@ lib.makeScope pkgs.newScope (self: {
     , editablePackageSources ? { }
     , extraPackages ? _ps: [ ]
     , groups ? [ "dev" ]
-    , checkGroups ? [ "dev" ]
+    , checkGroups ? checkGroupsDefault
     , extras ? [ "*" ]
     }:
     let
@@ -377,7 +379,7 @@ lib.makeScope pkgs.newScope (self: {
     , pwd ? projectDir
     , preferWheels ? false
     , groups ? [ ]
-    , checkGroups ? [ "dev" ]
+    , checkGroups ? checkGroupsDefault
     , extras ? [ "*" ]
     , ...
     }@attrs: