diff --git a/Makefile b/Makefile
index 43308b8..f0c303f 100644
--- a/Makefile
+++ b/Makefile
@@ -84,7 +84,7 @@ ALL += index
 ENV_VARS := ./engine/envvars.sh
 NIX_FILES := ./shell.nix  $(shell find nix -type f)
 $(ENV_VARS): $(NIX_FILES)
-	echo "export PATH=\"${PATH}\"" >> ./engine/envvars.sh
+	@echo "export PATH=\"${PATH}\"" >> ./engine/envvars.sh
 ALL += ./engine/envvars.sh
 
 # RSS
@@ -176,5 +176,6 @@ deploy: $(ALL)
 
 .PHONY: clean
 clean:
+	-[ -f $(ENV_VARS) ] && rm $(ENV_VARS)
 	-[ ! -z "$(DST_DIR)" ] && rm -rf $(DST_DIR)/*
 	-[ ! -z "$(CACHE_DIR)" ] && rm -rf $(CACHE_DIR)/*
diff --git a/engine/auto-build.sh b/engine/auto-build.sh
index 585bbed..1aefefc 100755
--- a/engine/auto-build.sh
+++ b/engine/auto-build.sh
@@ -1,5 +1,6 @@
 #!/usr/bin/env zsh
 cd "$(git rev-parse --show-toplevel)" || exit 1
+[[ -f ./engine/envvars.sh ]] || make ./engine/envvars.sh
 source ./engine/envvars.sh
 direnv reload
 ./engine/build.sh
diff --git a/engine/dev.sh b/engine/dev.sh
index a130f5d..71bb4b5 100755
--- a/engine/dev.sh
+++ b/engine/dev.sh
@@ -1,6 +1,4 @@
-#!/bin/bash
-set -e
-tmux \
-  new-session './engine/serve.sh' \; \
-  split-window './engine/auto-build.sh' \;
+#!/usr/bin/env zsh
+
+tee >(lorri watch) >(./engine/serve.sh) >(./engine/auto-build.sh) >(sleep 1 && open 'http://127.0.0.1:3000')