Updated dockerfile

Dockerfile

@@ -1,28 +1,33 @@
-# -*- mode: dockerfile -*-
-ARG BASE_IMAGE=ekidd/rust-musl-builder:latest
+# ------------------------------------------------------------------------------
+# Cargo Build Stage
+# ------------------------------------------------------------------------------
 
-# Our first FROM statement declares the build environment.
-FROM ${BASE_IMAGE} AS builder
+FROM rust:latest as cargo-build
 
-# Cache our dependencies
-WORKDIR /home/rust/
-RUN USER=rust cargo new xkcd --bin
-WORKDIR /home/rust/xkcd
-COPY Cargo.* ./
-RUN cargo build --release && rm ./target/x86_64-unknown-linux-musl/release/deps/xkcd* && rm -rf ./src/
+WORKDIR /usr/src/xkcd
 
-# Add our source code.
-COPY . ./
+COPY Cargo.toml Cargo.toml
 
-# Fix permissions on source code.
-RUN sudo chown -R rust:rust /home/rust
+RUN mkdir src/
+
+RUN echo "fn main() {println!(\"if you see this, the build broke\")}" > src/main.rs
+
+RUN cargo build --release
+
+RUN rm -f target/release/deps/xkcd*
+
+COPY src src
 
-# Build our application.
 RUN cargo build --release
 
-# Runner
-FROM alpine:latest
-RUN apk --no-cache add ca-certificates
-COPY --from=builder /home/rust/xkcd/target/x86_64-unknown-linux-musl/release/xkcd /xkcd
+# ------------------------------------------------------------------------------
+# Final Stage
+# ------------------------------------------------------------------------------
+
+FROM debian:stable-slim
+
+RUN apt-get update && apt-get install ca-certificates -y
+
+COPY --from=cargo-build /usr/src/xkcd/target/release/xkcd .
 
-CMD /xkcd
+CMD ["./xkcd"]