Make arm faster build

docker/Dockerfile

@@ -1,26 +1,38 @@
-FROM docker.io/library/debian:latest AS builder
+# syntax=docker/dockerfile:1
 
-# First - build
 
-RUN apt update && apt install -y curl libssl-dev perl git gcc make
-RUN curl -sSf https://sh.rustup.rs | sh -s -- -y --no-modify-path --default-toolchain stable --profile minimal
+FROM --platform=$BUILDPLATFORM rust:bookworm AS builder
 
-WORKDIR /ew/
+ARG TARGETARCH
 
-COPY ./ ./
+WORKDIR /ew
 
-WORKDIR /ew/
+RUN apt-get update \
+ && case "$TARGETARCH" in \
+      amd64) echo x86_64-unknown-linux-gnu > /rust-target ;; \
+      arm64) apt-get install -y --no-install-recommends \
+                 gcc-aarch64-linux-gnu libc6-dev-arm64-cross \
+             && rustup target add aarch64-unknown-linux-gnu \
+             && echo aarch64-unknown-linux-gnu > /rust-target ;; \
+      *) echo "Unsupported TARGETARCH: $TARGETARCH" >&2; exit 1 ;; \
+    esac \
+ && rm -rf /var/lib/apt/lists/*
 
-RUN . "$HOME/.cargo/env" && cargo build --release
+ENV CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER=aarch64-linux-gnu-gcc \
+    CC_aarch64_unknown_linux_gnu=aarch64-linux-gnu-gcc \
+    AR_aarch64_unknown_linux_gnu=aarch64-linux-gnu-ar
 
-## Second - sort stuff idk
+COPY . .
+
+# Cache
+RUN --mount=type=cache,target=/usr/local/cargo/registry,sharing=locked \
+    --mount=type=cache,target=/ew/target,id=ew-target-${TARGETARCH},sharing=locked \
+    cargo build --release --target "$(cat /rust-target)" \
+ && cp "target/$(cat /rust-target)/release/ew" /usr/local/bin/ew
 
 FROM docker.io/library/debian:bookworm-slim
 
-RUN mkdir -p /root/ew/
-COPY --from=builder /ew/target/release/ew /root/ew/ew
-COPY ./docker/start.sh /root/ew/start.sh
-
-RUN chmod +x /root/ew/start.sh
+COPY --from=builder --chmod=755 /usr/local/bin/ew /root/ew/ew
+COPY --chmod=755 ./docker/start.sh /root/ew/start.sh
 
 ENTRYPOINT ["/root/ew/start.sh"]