diff --git a/etc/portage/env/rust-makeopts.conf b/etc/portage/env/conservative-makeopts.conf
similarity index 100%
rename from etc/portage/env/rust-makeopts.conf
rename to etc/portage/env/conservative-makeopts.conf
diff --git a/etc/portage/env/enable-ccache.conf b/etc/portage/env/enable-ccache.conf
deleted file mode 100644
index cedb851..0000000
--- a/etc/portage/env/enable-ccache.conf
+++ /dev/null
@@ -1,2 +0,0 @@
-FEATURES="ccache"
-CCACHE_DIR="/var/cache/ccache"
diff --git a/etc/portage/package.env/conservative-makeopts b/etc/portage/package.env/conservative-makeopts
new file mode 100644
index 0000000..52e4455
--- /dev/null
+++ b/etc/portage/package.env/conservative-makeopts
@@ -0,0 +1,4 @@
+dev-lang/rust conservative-makeopts.conf
+llvm-core/clang conservative-makeopts.conf
+www-client/firefox conservative-makeopts.conf
+
diff --git a/etc/portage/package.env/firefox b/etc/portage/package.env/firefox
deleted file mode 100644
index e67bb4c..0000000
--- a/etc/portage/package.env/firefox
+++ /dev/null
@@ -1 +0,0 @@
-www-client/firefox rust-makeopts.conf
diff --git a/etc/portage/package.env/gentoo-kernel b/etc/portage/package.env/gentoo-kernel
deleted file mode 100644
index 7a79e3a..0000000
--- a/etc/portage/package.env/gentoo-kernel
+++ /dev/null
@@ -1 +0,0 @@
-sys-kernel/gentoo-kernel enable-ccache.conf
diff --git a/etc/portage/package.env/rust b/etc/portage/package.env/rust
deleted file mode 100644
index f3c66cc..0000000
--- a/etc/portage/package.env/rust
+++ /dev/null
@@ -1 +0,0 @@
-dev-lang/rust rust-makeopts.conf