diff --git a/engine b/engine
index 985d33d..e0425e6 160000
--- a/engine
+++ b/engine
@@ -1 +1 @@
-Subproject commit 985d33dd519f2f52ae45778a932c983893a92167
+Subproject commit e0425e6108a1d965d9826e6496445b8b31a8010a
diff --git a/run-harness-bench.sh b/run-harness-bench.sh
index 790e21b..452cc2b 100755
--- a/run-harness-bench.sh
+++ b/run-harness-bench.sh
@@ -20,7 +20,8 @@ RESULTS="$BENCH_DIR/RESULTS-harness.md"
 TIMEOUT="${BENCH_TIMEOUT:-3000}"                # seconds per variant
 POLL=60
 GIT_ID=(-c user.email=bench@example.com -c user.name=bench)
-VARIANTS=(builder-adversary builder-adversary-min builder-adversary-stateless)
+VARIANTS=(builder-adversary builder-adversary-min builder-adversary-stateless builder-adversary-lean)
+[ $# -gt 0 ] && VARIANTS=("$@")   # run only the variants named on the command line, if any
 
 # pre-trust a work dir in ~/.claude.json so interactive claude (in tmux) skips the workspace-trust
 # dialog (--dangerously-skip-permissions only skips it for redirected/headless output). Atomic merge: