diff --git a/.gitignore b/.gitignore
index 350a4de3e..fb7530896 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,6 +13,9 @@ cabal-dev/
 .cache/
 .stack/
 .stack-work/
+.dev-port-http
+.dev-port-https
+.bash_history
 yesod-devel/
 .cabal-sandbox
 cabal.sandbox.config
diff --git a/Makefile b/Makefile
index 88173918c..ffaccd8d0 100644
--- a/Makefile
+++ b/Makefile
@@ -167,17 +167,18 @@ well-known/.well-known:
 
 .PHONY: serve-backend
 serve-backend:
-	export DEV_PORT_HTTP=`netstat -tulan | perl -le 'use strict;use warnings;my %p=();my $addr=qr((?:\d+.\d+.\d+.\d+|[0-9a-f:]+));while(<>){ if(m#$addr:(\d+)\s+$addr:(?:\d+|\*)\s+#) { $p{$1}=1 }}; my $port = 3000; $port++ while $p{$port}; print $port'` ; \
-	export DEV_PORT_HTTPS=`netstat -tulan | perl -le 'use strict;use warnings;my %p=();my $addr=qr((?:\d+.\d+.\d+.\d+|[0-9a-f:]+));while(<>){ if(m#$addr:(\d+)\s+$addr:(?:\d+|\*)\s+#) { $p{$1}=1 }}; my $port = 3443; $port++ while $p{$port}; print $port'` ; \
-	echo "bisschen mehr: ${DEV_PORT_HTTP}" ; \
-	$(MAKE) -- --containerized---serve-dev-backend DEV_PORT_HTTP=${DEV_PORT_HTTP} DEV_PORT_HTTPS=${DEV_PORT_HTTPS}
+	DEV_PORT_HTTP=`docker/backend/dev_port.pl 3000 | tee .dev-port-http` \
+	DEV_PORT_HTTPS=`docker/backend/dev_port.pl 3443 | tee .dev-port-https` \
+	$(MAKE) -- --containerized---serve-dev-backend DEV_PORT_HTTP=$${DEV_PORT_HTTP} DEV_PORT_HTTPS=$${DEV_PORT_HTTPS}
 .PHONY: --serve-dev-backend
---serve-dev-backend:
+--serve-dev-backend: start.sh
+	DEV_PORT_HTTP=`cat .dev-port-http` \
+	DEV_PORT_HTTPS=`cat .dev-port-https` \
 	./start.sh
 
 .PHONY: --compile-backend
 --compile-backend:
-	stack build --fast --profile --library-profiling --executable-profiling --flag uniworx:-library-only --copy-bins --local-bin-path $$(pwd)/bin $(stackopts)
+	stack build --fast --profile --library-profiling --executable-profiling --flag uniworx:-library-only --local-bin-path $$(pwd)/bin $(stackopts)
 
 .PHONY: --lint-backend
 --lint-backend:
diff --git a/docker/backend/Dockerfile b/docker/backend/Dockerfile
index 98f9f00f7..84be254aa 100644
--- a/docker/backend/Dockerfile
+++ b/docker/backend/Dockerfile
@@ -24,6 +24,5 @@ RUN stack build yesod-bin
 ENV FRADRIVE_MAKE_TARGET=serve-backend
 ENTRYPOINT make -- ${FRADRIVE_MAKE_TARGET} STACK_ROOT=${STACK_ROOT} IN_CONTAINER=true
 
-# export full develop port range
-ENV DEV_PORT=3000
-EXPOSE ${DEV_PORT}/tcp
\ No newline at end of file
+EXPOSE 3000/tcp
+EXPOSE 3443/tcp
\ No newline at end of file
diff --git a/docker/backend/dev_port.pl b/docker/backend/dev_port.pl
new file mode 100755
index 000000000..0d8faa0db
--- /dev/null
+++ b/docker/backend/dev_port.pl
@@ -0,0 +1,19 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+
+my $port = $ARGV[0];
+my $used_ports = `netstat -tulan`;
+
+my %p=();
+my $addr=qr((?:\d+.\d+.\d+.\d+|[0-9a-f:]+));
+for(split m/\R/, $used_ports) {
+    if(m#$addr:(\d+)\s+$addr:(?:\d+|\*)\s+#) {
+        $p{$1}=1;
+    }
+};
+
+$port++ while $p{$port};
+
+print $port
\ No newline at end of file
diff --git a/docker/backend/dev_port.sh b/docker/backend/dev_port.sh
deleted file mode 100644
index 1008a5f0a..000000000
--- a/docker/backend/dev_port.sh
+++ /dev/null
@@ -1 +0,0 @@
-netstat -tulan | perl -le 'use strict;use warnings;my %p=();my $addr=qr((?:\d+.\d+.\d+.\d+|[0-9a-f:]+));while(<>){ if(m#$addr:(\d+)\s+$addr:(?:\d+|*)\s+#) { $p{$1}=1 }}; my $port = 3000; $port++ while $p{$port}; print $port'
\ No newline at end of file
diff --git a/start.sh b/start.sh
index ae78372e9..223bdfe0b 100755
--- a/start.sh
+++ b/start.sh
@@ -41,7 +41,7 @@ then
   yesod devel -p "$DEV_PORT_HTTP" -q "$DEV_PORT_HTTPS" $@
 elif ! [ -z "$(which stack)" ]
 then
-  stack exec -- yesod devel -p "$DEV_PORT_HTTP" -q "$DEV_PORT_HTTPS" $@ --copy-bins --local-bin-path $(pwd)/bin
+  stack exec -- yesod devel -p "$DEV_PORT_HTTP" -q "$DEV_PORT_HTTPS" $@
 else
   exit 1
 fi