diff --git a/pyproject.toml b/pyproject.toml
index 0898c25..252f2e6 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -18,7 +18,7 @@ dependencies = [
 [tool.uv.sources]
 base-app = { git = "https://github.com/sortitionfoundation/base-app/", tag = "v0.2.0" }
 datahandling = { git = "https://github.com/sortitionfoundation/datahandling/", tag = "v0.1.0" }
-groupselect = { git = "https://github.com/sortitionfoundation/groupselect-lib", tag = "v0.3.0" }
+groupselect = { git = "https://github.com/sortitionfoundation/groupselect-lib", tag = "v0.4.0" }
 
 [dependency-groups]
 deployment = [
diff --git a/uv.lock b/uv.lock
index 49113cf..b45a232 100644
--- a/uv.lock
+++ b/uv.lock
@@ -40,8 +40,8 @@ wheels = [
 
 [[package]]
 name = "groupselect"
-version = "0.3.0"
-source = { git = "https://github.com/sortitionfoundation/groupselect-lib?tag=v0.3.0#60089e5d276d97bf01c4684f7f9cd6af2ed1d70b" }
+version = "0.4.0"
+source = { git = "https://github.com/sortitionfoundation/groupselect-lib?tag=v0.4.0#c9ac5d9185aa3a6ae30040f17aed522958e6b192" }
 dependencies = [
     { name = "numpy" },
 ]
@@ -77,7 +77,7 @@ dev = [
 requires-dist = [
     { name = "base-app", git = "https://github.com/sortitionfoundation/base-app/?tag=v0.2.0" },
     { name = "datahandling", git = "https://github.com/sortitionfoundation/datahandling/?tag=v0.1.0" },
-    { name = "groupselect", git = "https://github.com/sortitionfoundation/groupselect-lib?tag=v0.3.0" },
+    { name = "groupselect", git = "https://github.com/sortitionfoundation/groupselect-lib?tag=v0.4.0" },
     { name = "pandas", specifier = ">=2.3.3,<3.0.0" },
 ]