diff --git a/python-libcst.spec b/python-libcst.spec
index 0c69a39..d3b20b5 100644
--- a/python-libcst.spec
+++ b/python-libcst.spec
@@ -97,6 +97,7 @@ cd native
 %cargo_build
 }
 cd ..
+export CARGO_NET_OFFLINE=true PROFILE=release
 %python_build
 %endif
 
@@ -107,6 +108,7 @@ cd native
 %cargo_install
 }
 cd ..
+export CARGO_NET_OFFLINE=true PROFILE=release
 %python_install
 %python_expand %fdupes %{buildroot}%{$python_sitearch}
 %endif
diff --git a/vendor.tar.xz b/vendor.tar.xz
index fe68453..bc3eef8 100644
--- a/vendor.tar.xz
+++ b/vendor.tar.xz
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:9bb299695a933f47e65d2be722935f797b8664368fb86197dcf862429b23cbde
-size 15092116
+oid sha256:5afc1e7a9de484bcace395eb1c199c0f533aa4ec01aed24d4250e6f051f0fcef
+size 15127288