diff --git a/.gitignore b/.gitignore
index f5d01ab..d9947d9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,3 @@
-_*
+_cache/
 src/archive.org
 .direnv/
diff --git a/_full/.gitignore b/_full/.gitignore
new file mode 100644
index 0000000..f935021
--- /dev/null
+++ b/_full/.gitignore
@@ -0,0 +1 @@
+!.gitignore
diff --git a/_optim/.gitignore b/_optim/.gitignore
new file mode 100644
index 0000000..f935021
--- /dev/null
+++ b/_optim/.gitignore
@@ -0,0 +1 @@
+!.gitignore
diff --git a/_site/.gitignore b/_site/.gitignore
new file mode 100644
index 0000000..f935021
--- /dev/null
+++ b/_site/.gitignore
@@ -0,0 +1 @@
+!.gitignore
diff --git a/engine/clean.sh b/engine/clean.sh
index ba3317e..b7ed4e6 100755
--- a/engine/clean.sh
+++ b/engine/clean.sh
@@ -2,8 +2,8 @@
 
 cd "$(git rev-parse --show-toplevel)" || exit 1
 echo -n "* Clean site cache"
-find _site -mindepth 1 -delete
-find _full -mindepth 1 -delete
-find _optim -mindepth 1 -delete
+find _site -not -path "_site/.gitignore" -mindepth 1 -delete
+find _full -not -path "_full/.gitignore" -mindepth 1 -delete
+find _optim -not -path "_optim/.gitignore" -mindepth 1 -delete
 rm -rf _cache
 echo " [done]"