diff --git a/Makefile b/Makefile
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+# tatlock-ui — the repo's command surface (D-27).
+#
+# Flutter rather than Python, so there is no venv and no PYTHON here. The
+# reason the targets still exist under these names is the point of D-27: an
+# agent or a person can run `make test` in any repo in this workspace without
+# first working out which stack it is.
+
+.DEFAULT_GOAL := help
+
+.PHONY: help
+help: ## Show this help
+	@grep -hE '^[a-z][a-z0-9_-]*:.*?## ' $(MAKEFILE_LIST) \
+	  | awk 'BEGIN{FS=":.*?## "}{printf "  \033[36m%-14s\033[0m %s\n", $$1, $$2}'
+
+.PHONY: setup
+setup: ## Fetch package dependencies
+	flutter pub get
+
+.PHONY: test
+test: ## Run the widget and unit tests
+	flutter test
+
+.PHONY: lint
+lint: ## Static analysis (analysis_options.yaml at the repo root)
+	flutter analyze
+
+.PHONY: build
+build: ## Release build for the web target
+	flutter build web --release
+
+.PHONY: clean
+clean: ## Remove build artefacts and the pub cache for this project
+	flutter clean