Added cross compile configuration

.cargo/config.toml

@@ -0,0 +1,5 @@
+[target.armv7-unknown-linux-musleabi]
+linker = "arm-linux-gnueabi-gcc"
+
+[target.armv7-unknown-linux-musleabihf]
+linker = "arm-linux-gnueabihf-gcc"

Cargo.toml

@@ -12,3 +12,6 @@ log = "0.4.20"
 rppal = "0.14.1"
 spaceapi-dezentrale-client = { git = "https://github.com/dezentrale/spaceapi-rs.git", package = "spaceapi-dezentrale-client", branch = "main" }
 tokio = { version = "1.35.1", features = ["macros"] }
+
+[profile.release]
+strip = true

README.md

@@ -10,3 +10,25 @@ Please change `DOOR_PIN` accordingly.
 
 You need to provide the environment variables
 `SPACEAPI_URL` and `API_KEY`.
+
+## Build
+
+[Install stable version of rust](https://rustup.rs/) and run a regular cargo build:
+
+```sh
+cargo build
+```
+
+### Cross compile
+
+Install arm toolchain and *libmusl* for static linked binaries:
+
+```sh
+apt-get install gcc-arm-linux-gnueabihf musl-dev musl-tools
+```
+
+Build the application for raspberry pi:
+
+```sh
+cargo build --target=armv7-unknown-linux-musleabihf
+```

rust-toolchain

@@ -0,0 +1,4 @@
+[toolchain]
+channel = "stable"
+targets = ["armv7-unknown-linux-musleabihf"]
+profile = "default"