diff --git a/internal/app.go b/internal/app.go
index bac4a48..46ad4aa 100644
--- a/internal/app.go
+++ b/internal/app.go
@@ -9,11 +9,16 @@ import (
 	"strings"
 
 	"github.com/aws/aws-sdk-go-v2/aws"
+	"github.com/aws/aws-sdk-go-v2/service/ec2"
 	"github.com/aws/aws-sdk-go-v2/service/ecs"
 	ecsTypes "github.com/aws/aws-sdk-go-v2/service/ecs/types"
 	"github.com/spf13/viper"
 )
 
+type EC2Client interface {
+	DescribeInstances(ctx context.Context, params *ec2.DescribeInstancesInput, optFns ...func(*ec2.Options)) (*ec2.DescribeInstancesOutput, error)
+}
+
 type ECSClient interface {
 	ListClusters(ctx context.Context, params *ecs.ListClustersInput, optFns ...func(*ecs.Options)) (*ecs.ListClustersOutput, error)
 	ListServices(ctx context.Context, params *ecs.ListServicesInput, optFns ...func(*ecs.Options)) (*ecs.ListServicesOutput, error)
diff --git a/internal/internal.go b/internal/internal.go
index 4017dfc..d12a3ed 100644
--- a/internal/internal.go
+++ b/internal/internal.go
@@ -115,7 +115,7 @@ func getPlatformFamily(client ECSClient, clusterName string, task *ecsTypes.Task
 
 // getContainerInstanceOS describes the specified container instance and checks against the backing EC2 instance
 // to determine the platform.
-func getContainerInstanceOS(ecsClient ECSClient, ec2Client *ec2.Client, cluster string, containerInstanceArn string) (string, error) {
+func getContainerInstanceOS(ecsClient ECSClient, ec2Client EC2Client, cluster string, containerInstanceArn string) (string, error) {
 	res, err := ecsClient.DescribeContainerInstances(context.TODO(), &ecs.DescribeContainerInstancesInput{
 		Cluster: aws.String(cluster),
 		ContainerInstances: []string{