diff --git a/Dockerfile b/Dockerfile
index 9c52fa6..9b47c8b 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -3,4 +3,4 @@ RUN yum install jq -y
 COPY bin /opt/resource
 RUN chmod +x /opt/resource/check /opt/resource/config /opt/resource/in /opt/resource/out
 RUN rm -rf /tmp/*
-CMD ["--version"]
+ENTRYPOINT [ "/bin/bash" ]
diff --git a/bin/config b/bin/config
deleted file mode 100644
index 7510a14..0000000
--- a/bin/config
+++ /dev/null
@@ -1,39 +0,0 @@
-config=$(cat)
-
-#echo $config > /tmp/source_vars
-
-aws_access_key_id=$(echo "$config" | jq -r ".source.access_key_id")
-aws_secret_access_key=$(echo "$config" | jq -r ".source.secret_access_key")
-aws_region=$(echo "$config" | jq -r ".source.region_name")
-
-if [[ $aws_access_key_id && $aws_secret_access_key ]]; then
-    export AWS_ACCESS_KEY_ID=$aws_access_key_id
-    export AWS_SECRET_ACCESS_KEY=$aws_secret_access_key
-    export AWS_DEFAULT_REGION=$aws_region
-fi
-
-namespace=$(echo "$config" | jq -r ".source.namespace")
-
-if [ -z "$namespace" ]; then
-    log_error "mandatory configuration 'source.namespace' not set"
-    exit 1
-fi
-
-metric=$(echo "$config" | jq -r ".source.metric")
-if [ -z "$metric" ]; then
-    log_error "mandatory configuration 'source.metric' not set"
-    exit 1
-fi
-
-value=$(echo "$config" | jq -r '.params | if has("value") then .value else 1 end')
-#unit=$(echo "$config" | jq -r '.params | if has("unit") then .unit else "Count" end')
-unit="Count"
-
-dimensions="build_job_name=${BUILD_JOB_NAME},build_pipeline_name=${BUILD_PIPELINE_NAME},build_team_name=$BUILD_TEAM_NAME"
-dimensions_provided=$(echo "$config" | jq -r '.params.dimensions | to_entries | map([.key,.value] | join("=")) | join(",")')
-
-if [ "$dimensions_provided" ]; then
-  dimensions="${dimensions},${dimensions_provided}"
-fi
-
-version=$(echo "$config" | jq -r ".version")
diff --git a/bin/out b/bin/out
index b2ef29e..5fa3d73 100755
--- a/bin/out
+++ b/bin/out
@@ -1,34 +1,78 @@
 #!/usr/bin/env bash
-set -e
 
-red='\033[0;31m'
-green='\033[0;32m'
-nc='\033[0m'
+set -eu
+set -o pipefail
 
-log() {
-  args=("$@")
-  # shellcheck disable=SC2145
-  echo -e "${green} ${args[@]}${nc}" 1>&2
-}
+exec 3>&1 # make stdout available as fd 3 for the result
+exec 1>&2 # redirect all output to stderr for logging
 
-log_err() {
-  args=("$@")
-  # shellcheck disable=SC2145
-  echo -e "${red} ${args[@]}${nc}" 1>&2
-}
+source=$1
 
-cwd="$(cd "$(dirname "$0")" && pwd)"
+# Read inputs
+#source=$1
+payload=$(mktemp -t cloudwatch-metrics-out-request-payload.XXXXXX)
+cat >"$payload" <&0
 
-cd "$1"
+# Parse source config
+aws_access_key_id=$(jq -r '.source.aws_access_key_id // ""' <"$payload")
+aws_secret_access_key=$(jq -r '.source.aws_secret_access_key // ""' <"$payload")
+aws_region=$(jq -r '.source.aws_region // ""' <"$payload")
+namespace=$(jq -r '.source.namespace // ""' <"$payload")
+metric=$(jq -r '.source.metric // ""' <"$payload")
 
-# load config
-. "$cwd"/config
+# Parse param config
+value=$(jq -r '.params.value // "1"' <"$payload")
+unit=$(jq -r '.params.unit // "Count"' <"$payload")
+dimensions_provided=$(jq -r '.params.dimensions // empty | to_entries | map([.key,.value] | join("=")) | join(",")' <"$payload")
 
-export AWS_PAGER=""
+if [ -n "$aws_access_key_id" ]; then
+  export AWS_ACCESS_KEY_ID=$aws_access_key_id
+fi
+
+if [ -n "$aws_secret_access_key" ]; then
+  export AWS_SECRET_ACCESS_KEY=$aws_secret_access_key
+fi
+
+if [ -n "$aws_region" ]; then
+  export AWS_DEFAULT_REGION=$aws_region
+fi
+
+if [ -z "$namespace" ]; then
+  echo "mandatory configuration 'source.namespace' not set"
+  exit 1
+fi
+
+if [ -z "$metric" ]; then
+  echo "mandatory configuration 'source.metric' not set"
+  exit 1
+fi
 
-aws cloudwatch put-metric-data --namespace "$namespace" --metric-name "$metric" --value "$value" --unit "$unit" --dimensions "$dimensions"
+re='^[+-]?[0-9]+([.][0-9]+)?$'
+if ! [[ $value =~ $re ]] ; then
+   echo "optional configuration params.value is not a number (value is ${value})"
+   exit 1
+fi
+
+dimensions="build_job_name=${BUILD_JOB_NAME},build_pipeline_name=${BUILD_PIPELINE_NAME},build_team_name=${BUILD_TEAM_NAME}"
+
+if [ -n "$dimensions_provided" ]; then
+  dimensions="${dimensions},${dimensions_provided}"
+fi
+
+export AWS_PAGER=""
 
-log "placed AWS cloudwatch metric '${metric}' to namespace '${namespace}', dimensions: ${dimensions}"
+# see https://docs.aws.amazon.com/cli/latest/reference/cloudwatch/put-metric-data.html
+aws cloudwatch put-metric-data --namespace "$namespace" --metric-name "$metric" --value "$value" --unit "$unit" --dimensions "${dimensions}"
+msg="placed AWS cloudwatch metric '${metric}' to namespace '${namespace}', with dimensions: ${dimensions}"
 
-echo "{\"version\":{\"ref\":\"${version}\"}}"
-exit 0
+jq -n "{
+    version: {
+        ref: \"none\",
+    },
+    metadata: [
+        {
+            name: \"message\",
+            value: $(echo $msg | jq -R .),
+        }
+    ]
+}" >&3
diff --git a/test/stdin.json b/test/stdin.json
index f163146..e4ef131 100644
--- a/test/stdin.json
+++ b/test/stdin.json
@@ -2,15 +2,14 @@
   "source": {
     "aws_access_key_id": "$ACCESS_KEY_ID",
     "aws_secret_access_key": "$SECRET_ACCESS_KEY",
-    "region": "eu-west-2",
+    "aws_region": "eu-west-2",
     "namespace": "TestNamespace",
     "metric": "job_fails"
   },
   "params": {
     "dimensions": {
-      "foo": "bar",
-      "fuzz": "buzz"
-    },
-    "value": 0
+      "foo" : "bar",
+      "fuzz" : "buzz"
+    }
   }
 }
\ No newline at end of file
diff --git a/test/test-pipeline.yaml b/test/test-pipeline.yaml
index a84273c..173506d 100644
--- a/test/test-pipeline.yaml
+++ b/test/test-pipeline.yaml
@@ -4,16 +4,16 @@ resource_types:
   - name: cloudwatch-metrics
     type: docker-image
     source:
-      repository: ghcr.io/idrop/cloudwatch-metrics
-      tag: 0.0.0.3
+      repository: ghcr.io/idrop/cloudwatch-metrics/cloudwatch-metrics
+      tag: 0.0.9
 
 resources:
   - name: cloudwatch-metrics-fails
     type: cloudwatch-metrics
     source:
-      region_name: eu-west-2
-      access_key_id: ((aws_access_key_id))
-      secret_access_key: ((aws_secret_access_key))
+      aws_region: eu-west-2
+      aws_access_key_id: ((aws_access_key_id))
+      aws_secret_access_key: ((aws_secret_access_key))
       namespace: phil
       metric: fails
 
@@ -34,9 +34,4 @@ jobs:
               - |
                 exit 1
     on_failure:
-      timeout: 1m
       put: cloudwatch-metrics-fails
-      params:
-        dimensions:
-          foo: bar
-          fuzz: buzz
\ No newline at end of file