diff --git a/docker/Dockerfile b/docker/Dockerfile
index 0588b43..8e7618b 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -1,5 +1,6 @@
 # This image contains scripts for creating Hot Pocket contract clusters
 # on the developer machine for local development testing.
+# docker build -t hpdevkit .
 
 FROM ubuntu:focal as builder
 RUN apt-get update && apt-get install -y wget
@@ -10,6 +11,10 @@ WORKDIR /build
 RUN wget -O docker.deb https://download.docker.com/linux/ubuntu/dists/focal/pool/stable/amd64/docker-ce-cli_20.10.9~3-0~ubuntu-focal_amd64.deb
 RUN dpkg -x docker.deb docker-extracted
 
+# Download jq
+RUN wget -O jq https://github.com/stedolan/jq/releases/download/jq-1.6/jq-linux64
+RUN chmod +x jq
+
 # Set permissions for hot pocket devkit scripts.
 COPY scripts /build/scripts
 RUN chmod -R +x /build/scripts/*.sh
@@ -17,7 +22,4 @@ RUN chmod -R +x /build/scripts/*.sh
 FROM ubuntu:focal as runner
 COPY --from=builder /build/docker-extracted/usr/bin/docker /usr/bin/
 COPY --from=builder /build/scripts/cluster.sh /usr/bin/cluster
-
-# docker build -t hpdevkit .
-# docker run -it --rm --mount type=bind,src=/var/run/docker.sock,dst=/var/run/docker.sock hpdevkit cluster create 2
-# docker run -it --rm --mount type=bind,src=/var/run/docker.sock,dst=/var/run/docker.sock --mount type=bind,src=D:\evernode\hp-devkit\src,dst=/dep hpdevkit cluster deploy /dep
\ No newline at end of file
+COPY --from=builder /build/jq /usr/bin/jq
\ No newline at end of file
diff --git a/docker/scripts/cluster.sh b/docker/scripts/cluster.sh
index 464f711..7120e74 100644
--- a/docker/scripts/cluster.sh
+++ b/docker/scripts/cluster.sh
@@ -9,6 +9,7 @@ container_prefix=$CONTAINER_PREFIX
 volume_mount=$VOLUME_MOUNT
 bundle_mount=$BUNDLE_MOUNT
 hotpocket_image=$HOTPOCKET_IMAGE
+config_overrides_file=$CONFIG_OVERRIDES_FILE
 
 if [ "$command" = "create" ] || [ "$command" = "destroy" ] || [ "$command" = "start" ] || [ "$command" = "stop" ] ||
     [ "$command" = "logs" ] || [ "$command" = "sync" ] ; then
@@ -130,6 +131,16 @@ function sync_contract_bundle {
         rm -rf $contract_dir/ledger_fs/*  $contract_dir/contract_fs/*
         mkdir -p $contract_dir/contract_fs/seed
         cp -r $bundle_mount $contract_dir/contract_fs/seed/state
+
+        # Merge contract config overrides.
+        local cfg_file=$contract_dir/cfg/hp.cfg
+        local override_file=$contract_dir/contract_fs/seed/state/$config_overrides_file
+        if [ -f $override_file ] ; then
+            echo "Applying hp.cfg overrides"
+            jq -s '.[0] * .[1]' $cfg_file $override_file > $cfg_file.merged
+            mv $cfg_file.merged $cfg_file
+            rm $override_file
+        fi
     done
 }
 
diff --git a/windows/hpdevkit.ps1 b/windows/hpdevkit.ps1
index f65721a..d128ee6 100644
--- a/windows/hpdevkit.ps1
+++ b/windows/hpdevkit.ps1
@@ -11,6 +11,7 @@ $Network = "$($GlobalPrefix)_$($Cluster)_net"
 $ContainerPrefix = "$($GlobalPrefix)_$($Cluster)_con"
 $BundleMount = "$($VolumeMount)/contract_bundle"
 $DeploymentContainerName = "$($GlobalPrefix)_$($Cluster)_deploymanager"
+$ConfigOverridesFile = "$($GlobalPrefix)_overrides.cfg"
 
 function DevKitContainer([string]$Mode, [string]$Name, [switch]$Detached, [switch]$AutoRemove, [switch]$MountSock, [switch]$MountVolume, [string]$Cmd) {
 
@@ -32,8 +33,9 @@ function DevKitContainer([string]$Mode, [string]$Name, [switch]$Detached, [switc
     }
 
     # Env variables.
-    $Command += " -e CLUSTER=$($Cluster) -e CLUSTER_SIZE=$($ClusterSize) -e VOLUME=$($Volume) -e NETWORK=$($Network)"
+    $Command += " -e CLUSTER=$($Cluster) -e CLUSTER_SIZE=$($ClusterSize) -e DEFAULT_NODE=$($DefaultNode) -e VOLUME=$($Volume) -e NETWORK=$($Network)"
     $Command += " -e CONTAINER_PREFIX=$($ContainerPrefix) -e VOLUME_MOUNT=$($VolumeMount) -e BUNDLE_MOUNT=$($BundleMount) -e HOTPOCKET_IMAGE=$($HotPocketImage)"
+    $Command += " -e CONFIG_OVERRIDES_FILE=$($ConfigOverridesFile)"
 
     $Command += " $($DevKitImage)"
     if ($Cmd) {