diff --git a/.yamllint b/.yamllint
new file mode 100644
index 0000000..ac1de4c
--- /dev/null
+++ b/.yamllint
@@ -0,0 +1,6 @@
+extends: default
+
+rules:
+  line-length:
+    max: 120
+    level: warning
diff --git a/buildspec.yml b/buildspec.yml
index 30db118..7191312 100644
--- a/buildspec.yml
+++ b/buildspec.yml
@@ -1,3 +1,4 @@
+---
 version: 0.2
 
 env:
@@ -17,4 +18,5 @@ phases:
       - coverage run --source=. -m unittest discover -s spoptimize
       - coverage report
       - python scripts/validate-templates.py
+      - yamllint *.yml demo/*.yml
       - coveralls
diff --git a/demo/demo.yml b/demo/demo.yml
index 418f26f..4e8c368 100644
--- a/demo/demo.yml
+++ b/demo/demo.yml
@@ -1,9 +1,11 @@
+---
+
 AWSTemplateFormatVersion: 2010-09-09
 Description: Spoptimize Demo
 
 Parameters:
 
-  InstanceType: 
+  InstanceType:
     Description: EC2 Instance Type
     Type: String
     Default: t2.micro
@@ -85,17 +87,17 @@ Resources:
           SourceSecurityGroupId: !GetAtt ElbSecGrp.GroupId
 
   ## These would be used for a NLB
-  #EIP1:
+  # EIP1:
   #  Type: AWS::EC2::EIP
   #  Properties:
   #    Domain: VPC
-  #EIP2:
+  # EIP2:
   #  Type: AWS::EC2::EIP
   #  Properties:
   #    Domain: VPC
 
   Elb:
-    #DependsOn:
+    # DependsOn:
     #  - EIP1
     #  - EIP2
     Type: AWS::ElasticLoadBalancingV2::LoadBalancer
@@ -106,14 +108,14 @@ Resources:
       SecurityGroups:
         - !GetAtt ElbSecGrp.GroupId
       IpAddressType: ipv4
-      #SubnetMappings:
+      # SubnetMappings:
       #  - SubnetId: !Select [ 0 !Ref SubnetIds ]
       #    AllocationId: !GetAtt EIP1.AllocationId
       #  - SubnetId: !Select [ 1 !Ref SubnetIds ]
       #    AllocationId: !GetAtt EIP2.AllocationId
-      Subnets: 
-        - !Select [ 0, !Ref SubnetIds ]
-        - !Select [ 1, !Ref SubnetIds ]
+      Subnets:
+        - !Select [0, !Ref SubnetIds]
+        - !Select [1, !Ref SubnetIds]
 
   ElbTargetGroup:
     Type: AWS::ElasticLoadBalancingV2::TargetGroup
@@ -148,7 +150,7 @@ Resources:
   LaunchConfig:
     Type: AWS::AutoScaling::LaunchConfiguration
     Properties:
-      ImageId: !FindInMap [ Region2Ami, !Ref "AWS::Region", amzn2 ]
+      ImageId: !FindInMap [Region2Ami, !Ref "AWS::Region", amzn2]
       KeyName: !Ref Ec2Key
       InstanceType: !Ref InstanceType
       IamInstanceProfile: !Sub "arn:aws:iam::${AWS::AccountId}:instance-profile/base-ec2"
@@ -186,10 +188,10 @@ Resources:
       DesiredCapacity: 1
       MinSize: 0
       MaxSize: 12
-      VPCZoneIdentifier: 
-        - !Select [ 0, !Ref SubnetIds ]
-        - !Select [ 1, !Ref SubnetIds ]
-      MetricsCollection: 
+      VPCZoneIdentifier:
+        - !Select [0, !Ref SubnetIds]
+        - !Select [1, !Ref SubnetIds]
+      MetricsCollection:
         - Granularity: 1Minute
       HealthCheckGracePeriod: 120
       Cooldown: 180
diff --git a/iam-global.yml b/iam-global.yml
index b4d4ac7..185ad25 100644
--- a/iam-global.yml
+++ b/iam-global.yml
@@ -1,3 +1,5 @@
+---
+
 AWSTemplateFormatVersion: 2010-09-09
 Description: IAM Resources for Spoptimize
 
@@ -33,12 +35,12 @@ Resources:
       Path: !Ref RolePath
       AssumeRolePolicyDocument:
         Statement:
-        - Effect: Allow
-          Principal:
-            Service: states.amazonaws.com
-          Action: sts:AssumeRole
+          - Effect: Allow
+            Principal:
+              Service: states.amazonaws.com
+            Action: sts:AssumeRole
       ManagedPolicyArns:
-      - !Ref StateMachineManagedPolicy
+        - !Ref StateMachineManagedPolicy
 
   LambdaManagedPolicy:
     Type: AWS::IAM::ManagedPolicy
@@ -48,62 +50,62 @@ Resources:
       PolicyDocument:
         Version: '2012-10-17'
         Statement:
-        - Sid: AutoScaling
-          Effect: Allow
-          Action:
-            - autoscaling:Describe*
-            - autoscaling:SetDesiredCapacity
-            - autoscaling:AttachInstances
-            - autoscaling:TerminateInstanceInAutoScalingGroup
-            #- autoscaling:DetachInstances
-          Resource: "*"
-        - Sid: SpotRequests
-          Effect: Allow
-          Action:
-            #- ec2:RunInstances
-            - ec2:CancelSpotInstanceRequests
-            - ec2:CreateTags
-            - ec2:DescribeSpotInstanceRequests
-            - ec2:DescribeSpotPriceHistory
-            - ec2:DescribeInstances
-            - ec2:DescribeTags
-            - ec2:RequestSpotInstances
-            - ec2:TerminateInstances
-          Resource: "*"
-        - Sid: StepFnStart
-          Effect: Allow
-          Action:
-            - states:StartExecution
-          Resource: !Sub "arn:aws:states:${AWS::Region}:${AWS::AccountId}:stateMachine:${StackBasename}-*"
-        - Sid: StepFnDescribeExec
-          Effect: Allow
-          Action:
-            - states:DescribeExecution
-          Resource: !Sub "arn:aws:states:${AWS::Region}:${AWS::AccountId}:execution:${StackBasename}-*"
-        - Sid: DynamoDbLockTable
-          Effect: Allow
-          Action:
-            - dynamodb:DeleteItem
-            - dynamodb:GetItem
-            - dynamodb:PutItem
-          Resource: !Sub "arn:aws:dynamodb:*:${AWS::AccountId}:table/${StackBasename}-autoscaling-group-locks"
-        - Sid: PassEc2IamRole
-          Effect: Allow
-          Action: iam:PassRole
-          Resource: "*"
-          Condition:
-            StringEquals:
-              iam:PassedToService:
-                - ec2.amazonaws.com
-                - ec2.amazonaws.com.cn
-        - Sid: GetIamInstanceProfiles
-          Effect: Allow
-          Action: iam:GetInstanceProfile
-          Resource: "*"
-        - Sid: CreateSpotServiceRole
-          Effect: Allow
-          Action: iam:CreateServiceLinkedRole
-          Resource: !Sub "arn:aws:iam::${AWS::AccountId}:role/aws-service-role/spot.amazonaws.com/AWSServiceRoleForEC2Spot"
+          - Sid: AutoScaling
+            Effect: Allow
+            Action:
+              - autoscaling:Describe*
+              - autoscaling:SetDesiredCapacity
+              - autoscaling:AttachInstances
+              - autoscaling:TerminateInstanceInAutoScalingGroup
+              # - autoscaling:DetachInstances
+            Resource: "*"
+          - Sid: SpotRequests
+            Effect: Allow
+            Action:
+              # - ec2:RunInstances
+              - ec2:CancelSpotInstanceRequests
+              - ec2:CreateTags
+              - ec2:DescribeSpotInstanceRequests
+              - ec2:DescribeSpotPriceHistory
+              - ec2:DescribeInstances
+              - ec2:DescribeTags
+              - ec2:RequestSpotInstances
+              - ec2:TerminateInstances
+            Resource: "*"
+          - Sid: StepFnStart
+            Effect: Allow
+            Action:
+              - states:StartExecution
+            Resource: !Sub "arn:aws:states:${AWS::Region}:${AWS::AccountId}:stateMachine:${StackBasename}-*"
+          - Sid: StepFnDescribeExec
+            Effect: Allow
+            Action:
+              - states:DescribeExecution
+            Resource: !Sub "arn:aws:states:${AWS::Region}:${AWS::AccountId}:execution:${StackBasename}-*"
+          - Sid: DynamoDbLockTable
+            Effect: Allow
+            Action:
+              - dynamodb:DeleteItem
+              - dynamodb:GetItem
+              - dynamodb:PutItem
+            Resource: !Sub "arn:aws:dynamodb:*:${AWS::AccountId}:table/${StackBasename}-autoscaling-group-locks"
+          - Sid: PassEc2IamRole
+            Effect: Allow
+            Action: iam:PassRole
+            Resource: "*"
+            Condition:
+              StringEquals:
+                iam:PassedToService:
+                  - ec2.amazonaws.com
+                  - ec2.amazonaws.com.cn
+          - Sid: GetIamInstanceProfiles
+            Effect: Allow
+            Action: iam:GetInstanceProfile
+            Resource: "*"
+          - Sid: CreateSpotServiceRole
+            Effect: Allow
+            Action: iam:CreateServiceLinkedRole
+            Resource: !Sub "arn:aws:iam::${AWS::AccountId}:role/aws-service-role/spot.amazonaws.com/AWSServiceRoleForEC2Spot"
 
   LambdaExecRole:
     Type: AWS::IAM::Role
@@ -112,13 +114,13 @@ Resources:
       Path: !Ref RolePath
       AssumeRolePolicyDocument:
         Statement:
-        - Effect: Allow
-          Principal:
-            Service: lambda.amazonaws.com
-          Action: sts:AssumeRole
+          - Effect: Allow
+            Principal:
+              Service: lambda.amazonaws.com
+            Action: sts:AssumeRole
       ManagedPolicyArns:
-      - arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole
-      - !Ref LambdaManagedPolicy
+        - arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole
+        - !Ref LambdaManagedPolicy
 
 Outputs:
   StateMachineManagedPolicy:
diff --git a/requirements-dev.txt b/requirements-dev.txt
index f254a6a..b51f150 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -3,3 +3,4 @@ boto3
 coveralls
 coverage
 mock
+yamllint
diff --git a/sam.yml b/sam.yml
index 6290790..9193d33 100644
--- a/sam.yml
+++ b/sam.yml
@@ -1,3 +1,5 @@
+---
+
 AWSTemplateFormatVersion: 2010-09-09
 Description: Step Functions for Spoptimize
 Transform: AWS::Serverless-2016-10-31
@@ -26,7 +28,7 @@ Parameters:
     Default: ""
 
 Conditions:
-  NoAlarmNotifications: !Equals [ !Ref AlarmTopicName, "" ]
+  NoAlarmNotifications: !Equals [!Ref AlarmTopicName, ""]
 
 Globals:
   Function:
@@ -487,12 +489,12 @@ Resources:
       ComparisonOperator: GreaterThanThreshold
       Threshold: 0
       TreatMissingData: notBreaching
-      ActionsEnabled: !If [ NoAlarmNotifications, false, true ]
+      ActionsEnabled: !If [NoAlarmNotifications, false, true]
       AlarmActions:
         Fn::If:
           - NoAlarmNotifications
           - !Ref AWS::NoValue
-          - [ !Sub "arn:aws:sns:${AWS::Region}:${AWS::AccountId}:${AlarmTopicName}" ]
+          - [!Sub "arn:aws:sns:${AWS::Region}:${AWS::AccountId}:${AlarmTopicName}"]
 
   SpotRequestorTimedOutAlrm:
     Type: AWS::CloudWatch::Alarm
@@ -510,12 +512,12 @@ Resources:
       ComparisonOperator: GreaterThanThreshold
       Threshold: 0
       TreatMissingData: notBreaching
-      ActionsEnabled: !If [ NoAlarmNotifications, false, true ]
+      ActionsEnabled: !If [NoAlarmNotifications, false, true]
       AlarmActions:
         Fn::If:
           - NoAlarmNotifications
           - !Ref AWS::NoValue
-          - [ !Sub "arn:aws:sns:${AWS::Region}:${AWS::AccountId}:${AlarmTopicName}" ]
+          - [!Sub "arn:aws:sns:${AWS::Region}:${AWS::AccountId}:${AlarmTopicName}"]
 
 Outputs:
   SpotRequestorArn:
diff --git a/scripts/run-tests.sh b/scripts/run-tests.sh
index c577690..26b140d 100755
--- a/scripts/run-tests.sh
+++ b/scripts/run-tests.sh
@@ -21,6 +21,15 @@ if [ -e requirements.txt ]; then
     #pip install -t vendored -r requirements.txt
 fi
 
+yamllint_cmd='yamllint *.yml demo/*.yml'
+echo "Checking yaml files via: $yamllint_cmd"
+$yamllint_cmd
+echo
+
+echo
+python scripts/validate-templates.py
+echo
+
 test_cmd='coverage run --source=. -m unittest discover -s spoptimize -v' "$@"
 echo "Executing: $test_cmd" "$@"
 $test_cmd "$@"