Add jerbuild-run / jerbuild-test targets

ober

de98b50b998b989ccef1546417c1cfd3d058ea93

diff --git a/Makefile b/Makefile
index 5f9afdf..f35d7a2 100644
--- a/Makefile
+++ b/Makefile
@@ -5,7 +5,8 @@ TEMPLATE_DIR := $(HOME)/.git-templates
 HOOK_DIR := $(TEMPLATE_DIR)/hooks
 
 .PHONY: run test binary install clean linux linux-local docker \
-        verify-harden help install-native macos gitsafe-macos
+        verify-harden help install-native macos gitsafe-macos \
+        jerbuild-run jerbuild-test
 
 .DEFAULT_GOAL := help
 
@@ -21,6 +22,21 @@ test:
 	JERBOA_HOME=$(JERBOA_HOME) \
 		$(SCHEME) -q --libdirs $(CURDIR):$(JERBOA_HOME)/lib --script test/test-gitsafe.ss
 
+# ── jerbuild path: standalone, no jerboa checkout required ───────────────────
+# Uses a single self-contained `jerbuild` binary (Chez + Jerboa stdlib bundled).
+# Override JERBUILD=/path/to/jerbuild to point at it.
+JERBUILD ?= jerbuild
+
+jerbuild-run:
+	@JH=$$($(JERBUILD) --jerboa-home); \
+	  env -u JERBOA_HOME $(JERBUILD) exec \
+	    --libdirs $(CURDIR):$$JH/lib gitsafe/main.ss -- $(ARGS)
+
+jerbuild-test:
+	@JH=$$($(JERBUILD) --jerboa-home); \
+	  env -u JERBOA_HOME $(JERBUILD) exec \
+	    --libdirs $(CURDIR):$$JH/lib test/test-gitsafe.ss
+
 install: $(if $(filter Darwin,$(shell uname -s)),gitsafe-macos,linux)
 	mkdir -p $(BIN_DIR)
 ifeq ($(shell uname -s),Darwin)