diff --git a/legacy/.gemini/policies/nix-build.toml b/legacy/.gemini/policies/nix-build.toml
new file mode 100644
index 0000000..928c557
--- /dev/null
+++ b/legacy/.gemini/policies/nix-build.toml
@@ -0,0 +1,5 @@
+[[rule]]
+toolName = "run_shell_command"
+commandPrefix = "nix build"
+decision = "allow"
+priority = 100