Add earthfile compiling

.earthignore

@@ -0,0 +1,3 @@
+*
+!/src
+!/Cargo.*

Cargo.toml

@@ -14,3 +14,13 @@ tui = "0.14"
 termion = "1.5"
 serde = {version = "1.0", features = ["derive"]}
 confy = "0.4.0"
+
+# TODO: cross compilation
+# [target.arm-unknown-linux-gnueabihf]
+# linker = "arm-linux-gnueabihf-gcc"
+
+# [target.armv7-unknown-linux-musleabi]
+# linker = "armv7-unknown-linux-musleabi-gcc"
+
+# [target.aarch64-unknown-linux-musl]
+# linker = "aarch64-unknown-linux-musl-gcc"

build.earth

@@ -0,0 +1,30 @@
+FROM rust:latest
+ENV CARGO_HOME=/deps
+WORKDIR /work
+RUN apt-get update
+RUN apt-get install -y gcc-arm-linux-gnueabi gcc-aarch64-linux-gnu
+
+deps:
+	COPY ./Cargo.toml ./Cargo.lock .
+	RUN mkdir src && touch src/main.rs
+	RUN cargo fetch
+	SAVE ARTIFACT /deps
+
+build:
+	ARG TOOLCHAIN
+	RUN rustup target add $TOOLCHAIN
+	SAVE IMAGE docker-wg:5000/rust-builder:$TOOLCHAIN
+
+	COPY +deps/deps /deps
+	COPY ./Cargo.toml ./Cargo.lock .
+	COPY ./src/ ./src/
+	RUN cargo build --release --target $TOOLCHAIN
+	SAVE ARTIFACT target/$TOOLCHAIN/release/rpn_rs AS LOCAL target/$TOOLCHAIN/release/rpn_rs
+
+all:
+	BUILD --build-arg TOOLCHAIN=x86_64-unknown-linux-musl +build
+	BUILD --build-arg TOOLCHAIN=i686-unknown-linux-musl +build
+	# TODO: Cross compile
+	# BUILD --build-arg TOOLCHAIN=aarch64-unknown-linux-musl +build
+	# BUILD --build-arg TOOLCHAIN=arm-unknown-linux-musleabi +build
+	# BUILD --build-arg TOOLCHAIN=armv7-unknown-linux-musleabi +build