diff --git a/terraform/aws/nodes.tf b/terraform/aws/nodes.tf
index d4f0806..11d668f 100644
--- a/terraform/aws/nodes.tf
+++ b/terraform/aws/nodes.tf
@@ -38,6 +38,8 @@ resource "aws_eks_node_group" "core_nodes" {
 
   instance_types = [var.instance_type]
 
+  capacity_type = var.capacity_type
+
   scaling_config {
     desired_size = 1
     max_size     = var.max_instances
@@ -59,4 +61,4 @@ resource "aws_eks_node_group" "core_nodes" {
     aws_iam_role_policy_attachment.node_worker_cni_policy_attachment,
     aws_iam_role_policy_attachment.node_worker_ecr_policy_attachment
   ]
-}
\ No newline at end of file
+}
diff --git a/terraform/aws/variables.tf b/terraform/aws/variables.tf
index 6501e88..2852c62 100644
--- a/terraform/aws/variables.tf
+++ b/terraform/aws/variables.tf
@@ -19,6 +19,18 @@ variable "instance_type" {
   EOT
 }
 
+variable "capacity_type" {
+  default     = "ON_DEMAND"
+  description = <<-EOT
+  Whether to use ON_DEMAND or SPOT instances.
+  EOT
+  
+  validation {
+    condition     = contains(["ON_DEMAND", "SPOT"], var.capacity_type)
+    error_message = "The capcity_type value must be ON_DEMAND or SPOT."
+  }
+}
+
 variable "max_instances" {
   default     = 10
   type        = number