diff --git a/nix/libstore/build.cc b/nix/libstore/build.cc
index c6615865be931d3584c024cbc332cabff9cd9442..693fa70c8d5e264f23ca0b21854849897872fe6b 100644
--- a/nix/libstore/build.cc
+++ b/nix/libstore/build.cc
@@ -2008,7 +2008,11 @@ void DerivationGoal::startBuilder()
 	char stack[32 * 1024];
 	int flags = CLONE_NEWPID | CLONE_NEWNS | CLONE_NEWIPC | CLONE_NEWUTS | SIGCHLD;
 	if (!fixedOutput) flags |= CLONE_NEWNET;
-	pid = clone(childEntry, stack + sizeof(stack) - 8, flags, this);
+#ifdef __aarch64__
+	    pid = clone(childEntry, stack + sizeof(stack) - 16, flags, this);
+#else
+	    pid = clone(childEntry, stack + sizeof(stack) - 8, flags, this);
+#endif
 	if (pid == -1)
 	    throw SysError("cloning builder process");
     } else