diff --git a/Makefile b/Makefile
index 2efeeda..3238223 100644
--- a/Makefile
+++ b/Makefile
@@ -41,7 +41,7 @@ SEARCH_Q     ?= computer
         textbooks-summary textbooks-urls fetch-textbooks textbooks-stats textbooks-verify \
         crawl-textbooks crawl-textbooks-stats textbook textbook-list bench-jaggedness \
         monitor-poll monitor-graph monitor-access \
-        bootstrap-object-store cold-pack cold-pack-dvd cold-unpack cold-stats cold-list
+        bootstrap-object-store cold-pack cold-pack-dvd cold-pack-all cold-pack-all-dvd cold-unpack cold-stats cold-list
 
 all: bootstrap fetch-cur ingest-cur verify stats ## bootstrap → fetch cur → ingest cur → verify → stats
 
@@ -886,6 +886,33 @@ cold-stats: bootstrap ## bucket summary: pack count, total bytes, endpoint
 cold-list: bootstrap ## enumerate packs (pack_hash, size, chunk_count) for new-peer hydration
 	$(ARBORIST) --db $(DB) cold list
 
+# Per-shard parallel pack run. Shards are independent SQLite files; packing
+# them in parallel scales near-linearly with CPU/network up to ~4 workers
+# (bench: single shard 100k chunks → 40 s build + 13 s upload; 4 shards
+# parallel ≈ same wall-clock for ~4x the corpus). SHARDS_DIR defaults to
+# ~/.arborist/shards; SHARDS_PATTERN filters which shard DBs participate.
+SHARDS_DIR     ?= $(HOME)/.arborist/shards
+SHARDS_PATTERN ?= [0-9][0-9][0-9].db
+COLD_PACK_JOBS ?= 4
+
+cold-pack-all: bootstrap ## parallel cold-pack across every shard (SHARDS_DIR, COLD_PACK_JOBS)
+	@echo ">> packing shards in $(SHARDS_DIR)/$(SHARDS_PATTERN) — $(COLD_PACK_JOBS)-way parallel"
+	@find $(SHARDS_DIR) -maxdepth 1 -name '$(SHARDS_PATTERN)' -print0 | \
+	    xargs -0 -n 1 -P $(COLD_PACK_JOBS) -I {} \
+	    $(ARBORIST) --db {} cold pack
+	@echo ">> all shards packed; final bucket state:"
+	@$(ARBORIST) cold stats
+
+cold-pack-all-dvd: bootstrap ## same fan-out but local-dir for DVD burning (no S3 push)
+	@if [ -z "$(LOCAL_DIR)" ]; then echo "LOCAL_DIR=<dir> required"; exit 2; fi
+	@mkdir -p $(LOCAL_DIR)
+	@echo ">> packing shards in $(SHARDS_DIR)/$(SHARDS_PATTERN) to $(LOCAL_DIR) — $(COLD_PACK_JOBS)-way parallel, no S3"
+	@find $(SHARDS_DIR) -maxdepth 1 -name '$(SHARDS_PATTERN)' -print0 | \
+	    xargs -0 -n 1 -P $(COLD_PACK_JOBS) -I {} \
+	    $(ARBORIST) --db {} cold pack --no-push --local-dir $(LOCAL_DIR)
+	@echo ">> all packs in $(LOCAL_DIR):"
+	@ls -lh $(LOCAL_DIR)/arborist-pack-*.tar.zst
+
 test: bootstrap ## run pytest suite (excludes opt-in crawler tests)
 	$(VENV)/bin/pytest -q --ignore=tests/crawler -n auto