diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..4fb998c
--- /dev/null
+++ b/.envrc
@@ -0,0 +1,11 @@
+#! /bin/sh
+
+# reload when these files change
+watch_file flake.nix
+watch_file flake.lock
+
+{
+  # shell gc root dir
+  mkdir -p "$(direnv_layout_dir)"
+  eval "$(nix print-dev-env --no-update-lock-file --no-write-lock-file --profile $(direnv_layout_dir)/flake-profile)"
+}
diff --git a/.gitignore b/.gitignore
index 5baca40..6726f97 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+/.direnv
 /result*
 /target/
 /tarpaulin*