Add distribution targets to Makefile.

Dockerfile

@@ -3,4 +3,3 @@ FROM scratch
 ENTRYPOINT ["/ktmpl"]
 
 COPY target/x86_64-unknown-linux-musl/release/ktmpl /ktmpl
-

Makefile

@@ -1,15 +1,37 @@
-all: cargo-build docker-build
+TAG = 0.2.1
 
-cargo-build:
+all: dist
+
+.PHONY: target/release/ktmpl
+target/release/ktmpl:
+	cargo build --release
+
+.PHONY: target/x86_64-unknown-linux-musl/release/ktmpl
+target/x86_64-unknown-linux-musl/release/ktmpl:
 	docker run \
 		--rm \
-		-v ${PWD}:/volume \
-		-v ${HOME}/.cargo/git:/root/.cargo/git \
-		-v ${HOME}/.cargo/registry:/root/.cargo/registry \
+		-v $(PWD):/volume \
+		-v $(HOME)/.cargo/git:/root/.cargo/git \
+		-v $(HOME)/.cargo/registry:/root/.cargo/registry \
 		-w /volume \
 		-t \
 		clux/muslrust \
 		cargo build --release
 
+.PHONY: docker-build
 docker-build:
-	docker build -t inquicker/ktmpl .
+	docker build -t inquicker/ktmpl -t inquicker/ktmpl:$(TAG) .
+
+dist: dist/sha256sums.txt.sig docker-build
+
+dist/ktmpl-$(TAG)-darwin.tar.gz: target/release/ktmpl
+	tar -c -C target/release -zvf dist/ktmpl-$(TAG)-darwin.tar.gz ktmpl
+
+dist/ktmpl-$(TAG)-linux.tar.gz: target/x86_64-unknown-linux-musl/release/ktmpl
+	tar -c -C target/x86_64-unknown-linux-musl/release -zvf dist/ktmpl-$(TAG)-linux.tar.gz ktmpl
+
+dist/sha256sums.txt: dist/ktmpl-$(TAG)-darwin.tar.gz dist/ktmpl-$(TAG)-linux.tar.gz
+	cd dist && shasum -a 256 * > sha256sums.txt
+
+dist/sha256sums.txt.sig: dist/sha256sums.txt
+	cd dist && gpg2 --detach-sign sha256sums.txt

README.md

@@ -69,6 +69,14 @@ docker pull inquicker/ktmpl
 
 Make sure Cargo's bin directory is added to your PATH environment variable.
 
+## Development
+
+To package the current release for distribution, update `TAG` in the Makefile and then run `make`.
+Release artifacts will be written to the `dist` directory.
+Docker images for `inquicker/ktmpl` and `inquicker/ktmpl:$TAG` will be created, but you must push
+them manually.
+Your GPG secret key will be required to sign `sha256sums.txt`.
+
 ## Legal
 
 ktmpl is released under the MIT license. See `LICENSE` for details.