diff --git a/cloud/services/loadbalancers.go b/cloud/services/loadbalancers.go
index a281ed7bf..c194a82a1 100644
--- a/cloud/services/loadbalancers.go
+++ b/cloud/services/loadbalancers.go
@@ -31,7 +31,11 @@ func CreateNodeBalancer(ctx context.Context, clusterScope *scope.ClusterScope, l
 		Label: NBLabel,
 		Tags:  tags,
 	}
-	linodeNBs, err := clusterScope.LinodeClient.ListNodeBalancers(ctx, linodego.NewListOptions(1, listFilter.String()))
+	filter, err := listFilter.String()
+	if err != nil {
+		return nil, err
+	}
+	linodeNBs, err := clusterScope.LinodeClient.ListNodeBalancers(ctx, linodego.NewListOptions(1, filter))
 	if err != nil {
 		logger.Info("Failed to list NodeBalancers", "error", err.Error())
 
diff --git a/controller/linodemachine_controller.go b/controller/linodemachine_controller.go
index 74fa36b6d..e8957888e 100644
--- a/controller/linodemachine_controller.go
+++ b/controller/linodemachine_controller.go
@@ -248,7 +248,11 @@ func (r *LinodeMachineReconciler) reconcileCreate(
 		Label: machineScope.LinodeMachine.Name,
 		Tags:  tags,
 	}
-	linodeInstances, err := machineScope.LinodeClient.ListInstances(ctx, linodego.NewListOptions(1, listFilter.String()))
+	filter, err := listFilter.String()
+	if err != nil {
+		return nil, err
+	}
+	linodeInstances, err := machineScope.LinodeClient.ListInstances(ctx, linodego.NewListOptions(1, filter))
 	if err != nil {
 		logger.Error(err, "Failed to list Linode machine instances")
 
diff --git a/controller/linodevpc_controller_helpers.go b/controller/linodevpc_controller_helpers.go
index 99eaf3552..e382bf33e 100644
--- a/controller/linodevpc_controller_helpers.go
+++ b/controller/linodevpc_controller_helpers.go
@@ -48,7 +48,11 @@ func (r *LinodeVPCReconciler) reconcileVPC(ctx context.Context, vpcScope *scope.
 		Label: createConfig.Label,
 		Tags:  nil,
 	}
-	if vpcs, err := vpcScope.LinodeClient.ListVPCs(ctx, linodego.NewListOptions(1, listFilter.String())); err != nil {
+	filter, err := listFilter.String()
+	if err != nil {
+		return err
+	}
+	if vpcs, err := vpcScope.LinodeClient.ListVPCs(ctx, linodego.NewListOptions(1, filter)); err != nil {
 		logger.Error(err, "Failed to list VPCs")
 
 		return err
diff --git a/util/filter.go b/util/filter.go
index 509f6dfe9..77aa972b3 100644
--- a/util/filter.go
+++ b/util/filter.go
@@ -35,11 +35,11 @@ func (f Filter) MarshalJSON() ([]byte, error) {
 
 // String returns the string representation of the encoded value from
 // [Filter.MarshalJSON].
-func (f Filter) String() string {
+func (f Filter) String() (string, error) {
 	p, err := f.MarshalJSON()
 	if err != nil {
-		panic("this should not have failed")
+		return "", err
 	}
 
-	return string(p)
+	return string(p), nil
 }
diff --git a/util/filter_test.go b/util/filter_test.go
new file mode 100644
index 000000000..c2d03c295
--- /dev/null
+++ b/util/filter_test.go
@@ -0,0 +1,54 @@
+package util
+
+import "testing"
+
+func TestString(t *testing.T) {
+	t.Parallel()
+	tests := []struct {
+		name      string
+		filter    Filter
+		expectErr bool
+	}{{
+		name: "success ID",
+		filter: Filter{
+			ID:    Pointer(123),
+			Label: "",
+			Tags:  nil,
+		},
+		expectErr: false,
+	}, {
+		name: "success label",
+		filter: Filter{
+			ID:    nil,
+			Label: "test",
+			Tags:  nil,
+		},
+		expectErr: false,
+	}, {
+		name: "success tags",
+		filter: Filter{
+			ID:    nil,
+			Label: "",
+			Tags:  []string{"testtag"},
+		},
+		expectErr: false,
+	}, {
+		name: "failure unmarshal",
+		filter: Filter{
+			ID:    nil,
+			Label: "",
+			Tags:  []string{},
+		},
+		expectErr: true,
+	}}
+	for _, tt := range tests {
+		testcase := tt
+		t.Run(testcase.name, func(t *testing.T) {
+			t.Parallel()
+			_, err := testcase.filter.String()
+			if testcase.expectErr && err != nil {
+				t.Error("expected err but got nil")
+			}
+		})
+	}
+}
diff --git a/version/version_test.go b/version/version_test.go
new file mode 100644
index 000000000..28581d2cb
--- /dev/null
+++ b/version/version_test.go
@@ -0,0 +1,11 @@
+package version
+
+import "testing"
+
+func TestVersion(t *testing.T) {
+	t.Parallel()
+	vers := GetVersion()
+	if vers != "dev" {
+		t.Errorf("unset version should be dev, got %s", vers)
+	}
+}