diff --git a/lix/libstore/build/local-derivation-goal.cc b/lix/libstore/build/local-derivation-goal.cc
index 1f41f9726..967f3c4b8 100644
--- a/lix/libstore/build/local-derivation-goal.cc
+++ b/lix/libstore/build/local-derivation-goal.cc
@@ -489,6 +489,11 @@ try {
         false,
         0700
     );
+    /* The TOCTOU between the previous mkdir call and this open call is unavoidable due to
+     * POSIX semantics.*/
+    tmpDirFd = AutoCloseFD{open(tmpDir.c_str(), O_RDONLY | O_NOFOLLOW | O_DIRECTORY)};
+    if (!tmpDirFd)
+        throw SysError("failed to open the build temporary directory descriptor '%1%'", tmpDir);
 
     chownToBuilder(tmpDir);
 
diff --git a/lix/libstore/build/local-derivation-goal.hh b/lix/libstore/build/local-derivation-goal.hh
index 239574673..b4be21721 100644
--- a/lix/libstore/build/local-derivation-goal.hh
+++ b/lix/libstore/build/local-derivation-goal.hh
@@ -31,6 +31,11 @@ struct LocalDerivationGoal : public DerivationGoal
      */
     Path tmpDir;
 
+    /**
+     * The temporary directory file descriptor
+     */
+    AutoCloseFD tmpDirFd;
+
     /**
      * The path of the temporary directory in the sandbox.
      */