diff --git a/.travis.yml b/.travis.yml
index 13e6ce0..05d13ef 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,9 +2,10 @@
 language: bash
 dist: xenial
 
-addons:
-  snaps:
-    - terraform
+before_install:
+  - curl -sLo /tmp/terraform.zip https://releases.hashicorp.com/terraform/0.12.2/terraform_0.12.2_linux_amd64.zip
+  - unzip /tmp/terraform.zip -d /tmp
+  - sudo mv /tmp/terraform /usr/local/bin/
 
 env:
   - AWS_REGION=us-east-1
diff --git a/README.md b/README.md
index 5cb1dee..523a25e 100644
--- a/README.md
+++ b/README.md
@@ -40,7 +40,7 @@ You can literally copy and paste the following example, change the following att
 ```hcl
 # include this module and enter the values of input variables
 module "ecs-gitlab" {
-  source              = "github.com/riboseinc/terraform-aws-ecs-gitlab"
+  source              = "riboseinc/ecs-gitlab/aws"
   gitlab_domain       = "gitlab.example.com"
   prefix              = "ribose"
   aws_ecs_cluster_id  = "arn:..."
@@ -49,11 +49,11 @@ module "ecs-gitlab" {
   certificate_arn     = "arn:..."
 }
 
-output "Root Password" {
-  value = "${module.ecs-gitlab.gitlab_root_password}"
+output "Root_Password" {
+  value = module.ecs-gitlab.gitlab_root_password
 }
 
-output "Gitlab Address" {
-  value = "${module.ecs-gitlab.gitlab_web_endpoint}"
+output "Gitlab_Address" {
+  value = module.ecs-gitlab.gitlab_web_endpoint
 }
 ```
diff --git a/main.tf b/main.tf
index a885e0f..4d7cd5b 100644
--- a/main.tf
+++ b/main.tf
@@ -1,25 +1,12 @@
 terraform {
-  required_version = "~> 0.11"
-}
-
-provider "aws" {
-  version = "~> 1.56"
-}
-
-provider "local" {
-  version = "~> 1.1"
-}
-
-provider "random" {
-  version = "~> 2.0"
-}
-
-provider "template" {
-  version = "~> 2.0"
-}
-
-provider "tls" {
-  version = "~> 1.2"
+  required_version = ">= 0.12"
+  required_providers {
+    aws      = "~> 2.16"
+    local    = "~> 1.2"
+    random   = "~> 2.1"
+    template = "~> 2.1"
+    tls      = "~> 2.0"
+  }
 }
 
 data "aws_region" "current" {}
diff --git a/resource-ec2.tf b/resource-ec2.tf
index b6dc092..1ad817e 100644
--- a/resource-ec2.tf
+++ b/resource-ec2.tf
@@ -1,4 +1,4 @@
 resource "aws_key_pair" "runners" {
   key_name_prefix = "${var.prefix}-runners"
-  public_key      = "${tls_private_key.runners-ssh.public_key_openssh}"
+  public_key      = tls_private_key.runners-ssh.public_key_openssh
 }
diff --git a/resource-ecs.tf b/resource-ecs.tf
index 129d7ee..2186bd6 100644
--- a/resource-ecs.tf
+++ b/resource-ecs.tf
@@ -5,7 +5,7 @@ resource "random_string" "gitlab_root_password" {
   number = true
 
   keepers = {
-    rds_id = "${aws_db_instance.main.id}"
+    rds_id = aws_db_instance.main.id
   }
 }
 
@@ -25,8 +25,8 @@ resource "aws_ecs_task_definition" "gitlab" {
   family                   = "gitlab-${random_id.ecs_id.hex}"
   requires_compatibilities = ["EC2"]
   network_mode             = "bridge"
-  task_role_arn            = "${aws_iam_role.ecs_task.arn}"
-  execution_role_arn       = "${aws_iam_role.ecs_task.arn}"
+  task_role_arn            = aws_iam_role.ecs_task.arn
+  execution_role_arn       = aws_iam_role.ecs_task.arn
   cpu                      = 2048
   memory                   = 4096
 
@@ -196,20 +196,21 @@ resource "aws_ecs_task_definition" "gitlab" {
         ]
       }
     ]
-    EOF
+EOF
+
 
   volume {
     name = "gitlab-${random_id.ecs_id.hex}-server-data"
 
     docker_volume_configuration {
       autoprovision = true
-      scope         = "shared"
-      driver        = "local"
+      scope = "shared"
+      driver = "local"
 
-      driver_opts {
-        type   = "nfs"
+      driver_opts = {
+        type = "nfs"
         device = "${aws_efs_file_system.gitlab.dns_name}:/server/data"
-        o      = "addr=${aws_efs_file_system.gitlab.dns_name},nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport"
+        o = "addr=${aws_efs_file_system.gitlab.dns_name},nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport"
       }
     }
   }
@@ -219,13 +220,13 @@ resource "aws_ecs_task_definition" "gitlab" {
 
     docker_volume_configuration {
       autoprovision = true
-      scope         = "shared"
-      driver        = "local"
+      scope = "shared"
+      driver = "local"
 
-      driver_opts {
-        type   = "nfs"
+      driver_opts = {
+        type = "nfs"
         device = "${aws_efs_file_system.gitlab.dns_name}:/server/config"
-        o      = "addr=${aws_efs_file_system.gitlab.dns_name},nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport"
+        o = "addr=${aws_efs_file_system.gitlab.dns_name},nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport"
       }
     }
   }
@@ -235,13 +236,13 @@ resource "aws_ecs_task_definition" "gitlab" {
 
     docker_volume_configuration {
       autoprovision = true
-      scope         = "shared"
-      driver        = "local"
+      scope = "shared"
+      driver = "local"
 
-      driver_opts {
-        type   = "nfs"
+      driver_opts = {
+        type = "nfs"
         device = "${aws_efs_file_system.gitlab.dns_name}:/runner"
-        o      = "addr=${aws_efs_file_system.gitlab.dns_name},nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport"
+        o = "addr=${aws_efs_file_system.gitlab.dns_name},nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport"
       }
     }
   }
@@ -251,35 +252,35 @@ resource "aws_ecs_task_definition" "gitlab" {
 
     docker_volume_configuration {
       autoprovision = true
-      scope         = "shared"
-      driver        = "local"
+      scope = "shared"
+      driver = "local"
 
-      driver_opts {
-        type   = "nfs"
+      driver_opts = {
+        type = "nfs"
         device = "${aws_efs_file_system.gitlab.dns_name}:/"
-        o      = "addr=${aws_efs_file_system.gitlab.dns_name},nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport"
+        o = "addr=${aws_efs_file_system.gitlab.dns_name},nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport"
       }
     }
   }
 }
 
 resource "aws_ecs_service" "gitlab" {
-  name                               = "${var.prefix}-gitlab-${random_id.ecs_id.hex}"
-  cluster                            = "${var.aws_ecs_cluster_id}"
-  task_definition                    = "${aws_ecs_task_definition.gitlab.arn}"
-  desired_count                      = 1
-  launch_type                        = "EC2"
-  iam_role                           = "${aws_iam_role.ecs_service.arn}"
+  name = "${var.prefix}-gitlab-${random_id.ecs_id.hex}"
+  cluster = var.aws_ecs_cluster_id
+  task_definition = aws_ecs_task_definition.gitlab.arn
+  desired_count = 1
+  launch_type = "EC2"
+  iam_role = aws_iam_role.ecs_service.arn
   deployment_minimum_healthy_percent = 0
-  deployment_maximum_percent         = 100
+  deployment_maximum_percent = 100
 
   load_balancer {
-    target_group_arn = "${aws_lb_target_group.http.arn}"
-    container_name   = "gitlab-server"
-    container_port   = 80
+    target_group_arn = aws_lb_target_group.http.arn
+    container_name = "gitlab-server"
+    container_port = 80
   }
 }
 
 output "gitlab_root_password" {
-  value = "${random_string.gitlab_root_password.result}"
+  value = random_string.gitlab_root_password.result
 }
diff --git a/resource-efs.tf b/resource-efs.tf
index 932a270..1327987 100644
--- a/resource-efs.tf
+++ b/resource-efs.tf
@@ -1,14 +1,14 @@
 resource "aws_efs_file_system" "gitlab" {
-  creation_token = "${var.prefix}"
+  creation_token = var.prefix
 }
 
 resource "aws_efs_mount_target" "gitlab" {
-  count          = "${length(var.subnets)}"
-  file_system_id = "${aws_efs_file_system.gitlab.id}"
-  subnet_id      = "${var.subnets[count.index]}"
+  count          = length(var.subnets)
+  file_system_id = aws_efs_file_system.gitlab.id
+  subnet_id      = var.subnets[count.index]
 
   security_groups = [
-    "${aws_security_group.allow_all_egress.id}",
-    "${aws_security_group.allow_all_subnets_vpc.id}",
+    aws_security_group.allow_all_egress.id,
+    aws_security_group.allow_all_subnets_vpc.id,
   ]
 }
diff --git a/resource-elasticache.tf b/resource-elasticache.tf
index 894ab3a..0ff7185 100644
--- a/resource-elasticache.tf
+++ b/resource-elasticache.tf
@@ -1,19 +1,19 @@
 resource "aws_elasticache_subnet_group" "main" {
-  name       = "${var.prefix}"
-  subnet_ids = ["${var.subnets}"]
+  name       = var.prefix
+  subnet_ids = var.subnets
 }
 
 resource "aws_elasticache_cluster" "main" {
   engine            = "redis"
-  engine_version    = "${var.elasticache["version"]}"
+  engine_version    = var.elasticache["version"]
   port              = 6379
-  cluster_id        = "${var.prefix}"
-  node_type         = "${var.elasticache["node_type"]}"
+  cluster_id        = var.prefix
+  node_type         = var.elasticache["node_type"]
   num_cache_nodes   = 1
-  subnet_group_name = "${aws_elasticache_subnet_group.main.name}"
+  subnet_group_name = aws_elasticache_subnet_group.main.name
 
   security_group_ids = [
-    "${aws_security_group.allow_all_egress.id}",
-    "${aws_security_group.allow_redis.id}",
+    aws_security_group.allow_all_egress.id,
+    aws_security_group.allow_redis.id,
   ]
 }
diff --git a/resource-iam.tf b/resource-iam.tf
index 26cdbdc..a49231a 100644
--- a/resource-iam.tf
+++ b/resource-iam.tf
@@ -1,5 +1,5 @@
 resource "aws_iam_role" "ecs_task" {
-  name_prefix = "${var.prefix}"
+  name_prefix = var.prefix
 
   assume_role_policy = <<EOF
 {
@@ -19,16 +19,17 @@ resource "aws_iam_role" "ecs_task" {
   ]
 }
 EOF
+
 }
 
 resource "aws_iam_role_policy_attachment" "ecs_task" {
-  role       = "${aws_iam_role.ecs_task.name}"
+  role = aws_iam_role.ecs_task.name
   policy_arn = "arn:aws:iam::aws:policy/service-role/AmazonECSTaskExecutionRolePolicy"
 }
 
 resource "aws_iam_role_policy" "ecs_task" {
-  name_prefix = "${var.prefix}"
-  role        = "${aws_iam_role.ecs_task.id}"
+  name_prefix = var.prefix
+  role = aws_iam_role.ecs_task.id
 
   policy = <<EOF
 {
@@ -102,12 +103,13 @@ resource "aws_iam_role_policy" "ecs_task" {
   ]
 }
 EOF
+
 }
 
 resource "aws_iam_role" "ecs_service" {
-  name_prefix = "${var.prefix}"
+name_prefix = var.prefix
 
-  assume_role_policy = <<-EOF
+assume_role_policy = <<-EOF
   {
     "Version": "2012-10-17",
     "Statement": [
@@ -123,19 +125,20 @@ resource "aws_iam_role" "ecs_service" {
       }
     ]
   }
-  EOF
+EOF
+
 }
 
 resource "aws_iam_role_policy_attachment" "ecs_service" {
-  policy_arn = "arn:aws:iam::aws:policy/service-role/AmazonEC2ContainerServiceRole"
-  role       = "${aws_iam_role.ecs_service.id}"
+policy_arn = "arn:aws:iam::aws:policy/service-role/AmazonEC2ContainerServiceRole"
+role = aws_iam_role.ecs_service.id
 }
 
 resource "aws_iam_role_policy" "ecs_service" {
-  name_prefix = "${var.prefix}"
-  role        = "${aws_iam_role.ecs_service.id}"
+name_prefix = var.prefix
+role = aws_iam_role.ecs_service.id
 
-  policy = <<EOF
+policy = <<EOF
 {
   "Version": "2012-10-17",
   "Statement": [
@@ -152,6 +155,7 @@ resource "aws_iam_role_policy" "ecs_service" {
   ]
 }
 EOF
+
 }
 
 #
@@ -159,7 +163,7 @@ EOF
 #
 
 resource "aws_iam_role" "gitlab_runner_instance" {
-  name_prefix = "${var.prefix}"
+  name_prefix = var.prefix
 
   assume_role_policy = <<-EOF
   {
@@ -176,13 +180,14 @@ resource "aws_iam_role" "gitlab_runner_instance" {
       }
     ]
   }
-  EOF
+EOF
+
 }
 
 resource "aws_iam_instance_profile" "gitlab_runner_instance" {
-  name_prefix = "${var.prefix}"
-  path        = "/"
-  role        = "${aws_iam_role.gitlab_runner_instance.name}"
+  name_prefix = var.prefix
+  path = "/"
+  role = aws_iam_role.gitlab_runner_instance.name
 
   lifecycle {
     create_before_destroy = true
@@ -190,8 +195,8 @@ resource "aws_iam_instance_profile" "gitlab_runner_instance" {
 }
 
 resource "aws_iam_role_policy" "gitlab_runner_instance" {
-  name_prefix = "${var.prefix}"
-  role        = "${aws_iam_role.gitlab_runner_instance.id}"
+  name_prefix = var.prefix
+  role = aws_iam_role.gitlab_runner_instance.id
 
   policy = <<-EOF
   {
@@ -236,5 +241,6 @@ resource "aws_iam_role_policy" "gitlab_runner_instance" {
       }
     ]
   }
-  EOF
+EOF
+
 }
diff --git a/resource-lb.tf b/resource-lb.tf
index 09580c8..4d6ac2d 100644
--- a/resource-lb.tf
+++ b/resource-lb.tf
@@ -1,26 +1,26 @@
 resource "aws_iam_server_certificate" "gitlab" {
-  count            = "${var.certificate_self_signed == 1 ? 1 : 0}"
-  name_prefix      = "${var.prefix}"
-  certificate_body = "${tls_locally_signed_cert.gitlab.cert_pem}"
-  private_key      = "${tls_private_key.gitlab.private_key_pem}"
+  count            = var.certificate_self_signed ? 1 : 0
+  name_prefix      = var.prefix
+  certificate_body = tls_locally_signed_cert.gitlab[0].cert_pem
+  private_key      = tls_private_key.gitlab[0].private_key_pem
 }
 
 resource "aws_lb" "gitlab" {
-  name     = "${var.prefix}"
+  name     = var.prefix
   internal = false
-  subnets  = ["${var.subnets}"]
+  subnets  = var.subnets
 
   security_groups = [
-    "${aws_security_group.allow_all_egress.id}",
-    "${aws_security_group.allow_web_public.id}",
+    aws_security_group.allow_all_egress.id,
+    aws_security_group.allow_web_public.id,
   ]
 }
 
 resource "aws_lb_target_group" "http" {
-  name_prefix = "${replace(var.prefix, "/(.{0,6})(.*)/", "$1")}"
+  name_prefix = replace(var.prefix, "/(.{0,6})(.*)/", "$1")
   port        = 80
   protocol    = "HTTP"
-  vpc_id      = "${var.vpc_id}"
+  vpc_id      = var.vpc_id
 
   health_check {
     interval            = 60
@@ -34,29 +34,34 @@ resource "aws_lb_target_group" "http" {
 }
 
 resource "aws_lb_listener" "http" {
-  load_balancer_arn = "${aws_lb.gitlab.arn}"
+  load_balancer_arn = aws_lb.gitlab.arn
   port              = "80"
   protocol          = "HTTP"
 
   default_action {
-    target_group_arn = "${aws_lb_target_group.http.arn}"
-    type             = "forward"
+    type = "redirect"
+
+    redirect {
+      port        = "443"
+      protocol    = "HTTPS"
+      status_code = "HTTP_301"
+    }
   }
 }
 
 resource "aws_lb_listener" "https" {
-  load_balancer_arn = "${aws_lb.gitlab.arn}"
+  load_balancer_arn = aws_lb.gitlab.arn
   port              = "443"
   protocol          = "HTTPS"
-  ssl_policy        = "ELBSecurityPolicy-TLS-1-0-2015-04"
-  certificate_arn   = "${var.certificate_self_signed == 1 ? element(concat(aws_iam_server_certificate.gitlab.*.arn, list("")), 0) : var.certificate_arn}"
+  ssl_policy        = "ELBSecurityPolicy-TLS-1-2-2017-01"
+  certificate_arn   = var.certificate_self_signed ? element(concat(aws_iam_server_certificate.gitlab.*.arn, [""]), 0) : var.certificate_arn
 
   default_action {
-    target_group_arn = "${aws_lb_target_group.http.arn}"
+    target_group_arn = aws_lb_target_group.http.arn
     type             = "forward"
   }
 }
 
 output "gitlab_web_endpoint" {
-  value = "${local.gitlab_address}"
+  value = local.gitlab_address
 }
diff --git a/resource-rds.tf b/resource-rds.tf
index eb5fc9e..d5db460 100644
--- a/resource-rds.tf
+++ b/resource-rds.tf
@@ -7,36 +7,36 @@ resource "random_string" "gitlab_postgres_password" {
 }
 
 resource "aws_db_subnet_group" "main" {
-  name_prefix = "${var.prefix}"
-  subnet_ids  = ["${var.subnets}"]
+  name_prefix = var.prefix
+  subnet_ids  = var.subnets
 }
 
 resource "random_id" "rds" {
   keepers = {
-    ami_id = "${var.rds["database"]}"
+    ami_id = var.rds["database"]
   }
 
   byte_length = 8
 }
 
 resource "aws_db_instance" "main" {
-  name                      = "${var.rds["database"]}"
-  allocated_storage         = "${var.rds["allocated_storage"]}"
-  storage_type              = "${var.rds["storage_type"]}"
+  name                      = var.rds["database"]
+  allocated_storage         = var.rds["allocated_storage"]
+  storage_type              = var.rds["storage_type"]
   engine                    = "postgres"
-  engine_version            = "${var.rds["version"]}"
-  instance_class            = "${var.rds["instance_class"]}"
-  username                  = "${var.rds["username"]}"
-  password                  = "${random_string.gitlab_postgres_password.result}"
-  db_subnet_group_name      = "${aws_db_subnet_group.main.name}"
-  skip_final_snapshot       = "${var.rds["skip_final_snapshot"]}"
+  engine_version            = var.rds["version"]
+  instance_class            = var.rds["instance_class"]
+  username                  = var.rds["username"]
+  password                  = random_string.gitlab_postgres_password.result
+  db_subnet_group_name      = aws_db_subnet_group.main.name
+  skip_final_snapshot       = var.rds["skip_final_snapshot"]
   final_snapshot_identifier = "${var.prefix}-snapshot-postgresql-${var.rds["database"]}-${random_id.rds.hex}"
   backup_retention_period   = 3
   backup_window             = "02:00-03:00"
   maintenance_window        = "sun:03:01-sun:05:00"
 
   vpc_security_group_ids = [
-    "${aws_security_group.allow_all_egress.id}",
-    "${aws_security_group.allow_postgresql.id}",
+    aws_security_group.allow_all_egress.id,
+    aws_security_group.allow_postgresql.id,
   ]
 }
diff --git a/resource-s3.tf b/resource-s3.tf
index f065ebe..dc6ea01 100644
--- a/resource-s3.tf
+++ b/resource-s3.tf
@@ -6,3 +6,4 @@ resource "aws_s3_bucket" "gitlab" {
   bucket        = "${var.prefix}-gitlab-${random_id.s3-gitlab.hex}"
   force_destroy = true
 }
+
diff --git a/resource-security_groups.tf b/resource-security_groups.tf
index ebf209d..e36c5e4 100644
--- a/resource-security_groups.tf
+++ b/resource-security_groups.tf
@@ -1,12 +1,12 @@
 data "aws_subnet" "main" {
-  count = "${length(var.subnets)}"
-  id    = "${var.subnets[count.index]}"
+  count = length(var.subnets)
+  id    = var.subnets[count.index]
 }
 
 resource "aws_security_group" "allow_all_egress" {
-  name_prefix = "${var.prefix}"
+  name_prefix = var.prefix
   description = "Allow All Egress"
-  vpc_id      = "${var.vpc_id}"
+  vpc_id      = var.vpc_id
 
   egress {
     from_port   = 0
@@ -17,25 +17,23 @@ resource "aws_security_group" "allow_all_egress" {
 }
 
 resource "aws_security_group" "allow_postgresql" {
-  name_prefix = "${var.prefix}"
+  name_prefix = var.prefix
   description = "Allow PostgreSQL"
-  vpc_id      = "${var.vpc_id}"
+  vpc_id      = var.vpc_id
 
   ingress {
     from_port = 5432
     to_port   = 5432
     protocol  = "tcp"
 
-    cidr_blocks = [
-      "${data.aws_subnet.main.*.cidr_block}",
-    ]
+    cidr_blocks = data.aws_subnet.main.*.cidr_block
   }
 }
 
 resource "aws_security_group" "allow_web_public" {
-  name_prefix = "${var.prefix}"
+  name_prefix = var.prefix
   description = "Allow Web Public"
-  vpc_id      = "${var.vpc_id}"
+  vpc_id      = var.vpc_id
 
   ingress {
     from_port   = 80
@@ -53,41 +51,37 @@ resource "aws_security_group" "allow_web_public" {
 }
 
 resource "aws_security_group" "allow_all_subnets_vpc" {
-  name_prefix = "${var.prefix}"
+  name_prefix = var.prefix
   description = "Allow Web Private"
-  vpc_id      = "${var.vpc_id}"
+  vpc_id      = var.vpc_id
 
   ingress {
     from_port = 0
     to_port   = 0
     protocol  = "-1"
 
-    cidr_blocks = [
-      "${data.aws_subnet.main.*.cidr_block}",
-    ]
+    cidr_blocks = data.aws_subnet.main.*.cidr_block
   }
 }
 
 resource "aws_security_group" "allow_redis" {
-  name_prefix = "${var.prefix}"
+  name_prefix = var.prefix
   description = "Allow Redis"
-  vpc_id      = "${var.vpc_id}"
+  vpc_id      = var.vpc_id
 
   ingress {
     from_port = 6379
     to_port   = 6379
     protocol  = "tcp"
 
-    cidr_blocks = [
-      "${data.aws_subnet.main.*.cidr_block}",
-    ]
+    cidr_blocks = data.aws_subnet.main.*.cidr_block
   }
 }
 
 resource "aws_security_group" "allow_all_public" {
-  name_prefix = "${var.prefix}"
+  name_prefix = var.prefix
   description = "Allow all inbound traffic"
-  vpc_id      = "${var.vpc_id}"
+  vpc_id      = var.vpc_id
 
   ingress {
     from_port   = 0
@@ -105,9 +99,9 @@ resource "aws_security_group" "allow_all_public" {
 }
 
 resource "aws_security_group" "runner" {
-  name_prefix = "${var.prefix}"
+  name_prefix = var.prefix
   description = "Security group for gitlab runners"
-  vpc_id      = "${var.vpc_id}"
+  vpc_id      = var.vpc_id
 
   ingress {
     from_port   = 22
@@ -130,3 +124,4 @@ resource "aws_security_group" "runner" {
     cidr_blocks = ["0.0.0.0/0"]
   }
 }
+
diff --git a/resource-tls.tf b/resource-tls.tf
index 9220a72..96dedac 100644
--- a/resource-tls.tf
+++ b/resource-tls.tf
@@ -3,15 +3,15 @@
 #
 
 resource "tls_private_key" "ca" {
-  count       = "${var.certificate_self_signed == 1 ? 1 : 0}"
+  count       = var.certificate_self_signed ? 1 : 0
   algorithm   = "ECDSA"
   ecdsa_curve = "P384"
 }
 
 resource "tls_self_signed_cert" "ca" {
-  count                 = "${var.certificate_self_signed == 1 ? 1 : 0}"
+  count                 = var.certificate_self_signed ? 1 : 0
   key_algorithm         = "ECDSA"
-  private_key_pem       = "${tls_private_key.ca.private_key_pem}"
+  private_key_pem       = tls_private_key.ca[0].private_key_pem
   is_ca_certificate     = true
   validity_period_hours = 8760
 
@@ -20,8 +20,8 @@ resource "tls_self_signed_cert" "ca" {
   ]
 
   subject {
-    common_name  = "${var.prefix}"
-    organization = "${var.prefix}"
+    common_name  = var.prefix
+    organization = var.prefix
   }
 }
 
@@ -30,29 +30,29 @@ resource "tls_self_signed_cert" "ca" {
 #
 
 resource "tls_private_key" "gitlab" {
-  count       = "${var.certificate_self_signed == 1 ? 1 : 0}"
+  count       = var.certificate_self_signed ? 1 : 0
   algorithm   = "ECDSA"
   ecdsa_curve = "P384"
 }
 
 resource "tls_cert_request" "gitlab" {
-  count           = "${var.certificate_self_signed == 1 ? 1 : 0}"
+  count           = var.certificate_self_signed ? 1 : 0
   key_algorithm   = "ECDSA"
-  private_key_pem = "${tls_private_key.gitlab.private_key_pem}"
-  dns_names       = ["${local.gitlab_domain}"]
+  private_key_pem = tls_private_key.gitlab[0].private_key_pem
+  dns_names       = [local.gitlab_domain]
 
   subject {
-    common_name  = "${local.gitlab_domain}"
-    organization = "${var.prefix}"
+    common_name  = local.gitlab_domain
+    organization = var.prefix
   }
 }
 
 resource "tls_locally_signed_cert" "gitlab" {
-  count                 = "${var.certificate_self_signed == 1 ? 1 : 0}"
-  cert_request_pem      = "${tls_cert_request.gitlab.cert_request_pem}"
+  count                 = var.certificate_self_signed ? 1 : 0
+  cert_request_pem      = tls_cert_request.gitlab[0].cert_request_pem
   ca_key_algorithm      = "ECDSA"
-  ca_private_key_pem    = "${tls_private_key.ca.private_key_pem}"
-  ca_cert_pem           = "${tls_self_signed_cert.ca.cert_pem}"
+  ca_private_key_pem    = tls_private_key.ca[0].private_key_pem
+  ca_cert_pem           = tls_self_signed_cert.ca[0].cert_pem
   validity_period_hours = 8760
 
   allowed_uses = [
diff --git a/vars.tf b/vars.tf
index d8e0a52..99e73fc 100644
--- a/vars.tf
+++ b/vars.tf
@@ -16,7 +16,7 @@ variable "vpc_id" {
 
 # Minimum 2 subnets should be configured
 variable "subnets" {
-  type    = "list"
+  type    = list(string)
   default = []
 }
 
@@ -29,7 +29,7 @@ variable "certificate_arn" {
 }
 
 variable "gitlab_runners" {
-  type = "map"
+  type = map(string)
 
   default = {
     image          = "gitlab/gitlab-runner:latest"
@@ -44,7 +44,7 @@ variable "gitlab_runners" {
 }
 
 variable "elasticache" {
-  type = "map"
+  type = map(string)
 
   default = {
     node_type = "cache.t2.micro"
@@ -53,7 +53,7 @@ variable "elasticache" {
 }
 
 variable "rds" {
-  type = "map"
+  type = map(string)
 
   default = {
     allocated_storage   = 20
@@ -67,7 +67,7 @@ variable "rds" {
 }
 
 locals {
-  gitlab_domain  = "${var.gitlab_domain == "" ? aws_lb.gitlab.dns_name : var.gitlab_domain}"
+  gitlab_domain  = var.gitlab_domain == "" ? aws_lb.gitlab.dns_name : var.gitlab_domain
   gitlab_address = "https://${local.gitlab_domain}/"
 
   gitlab_omnibus_config = [
@@ -80,7 +80,7 @@ locals {
     "nginx['redirect_http_to_https'] = true",
     "nginx['proxy_set_headers'] = {'X-Forwarded-Proto' => 'https', 'X-Forwarded-Ssl' => 'on'}",
     "redis['enable'] = false",
-    "gitlab_rails['redis_host'] = '${aws_elasticache_cluster.main.cache_nodes.0.address}'",
+    "gitlab_rails['redis_host'] = '${aws_elasticache_cluster.main.cache_nodes[0].address}'",
     "gitlab_rails['redis_port'] = 6379",
     "postgresql['enable'] = false",
     "gitlab_rails['db_adapter'] = 'postgresql'",