Control the packages created by docker build with build args

Dockerfile

@@ -36,13 +36,14 @@ FROM builder-image AS build-stage
 WORKDIR /app
 COPY . .
 
-RUN make msix GOARCH=amd64 && \
-    make deb GOARCH=amd64 && \
-    make rpm GOARCH=amd64 && \
-    make osx GOARCH=amd64 && \
-    make deb GOARCH=arm64 && \
-    make rpm GOARCH=arm64 && \
-    make osx GOARCH=arm64
+ARG ARCH="amd64 arm64"
+ARG PACKAGE="msix deb rpm osx"
+RUN for arch in ${ARCH}; do \
+      for pkg in ${PACKAGE}; do \
+        [ $pkg != msix -o $arch == amd64 ] || continue; \
+        make $pkg GOARCH=$arch || exit 1; \
+      done; \
+    done
 
 FROM scratch AS build-artifacts
 COPY --from=build-stage /app/dist /

README.md

@@ -82,23 +82,48 @@ can be targeted by name when running `corteca exec`.
 
 ## Build
 
-Clone the repository and run:
+### Building Locally
+
+To build locally, you need to have a Go toolchain installed. Clone the repository and run:
 
 ```bash
 $ make
 ```
 
-The compiled binary is placed in the `dist/` directory.
+The compiled binary is placed in the `dist/` directory. You can also build packages for your specific platform. The available `make` targets are `deb`, `rpm`, `osx` and `msix`:
+
+```bash
+$ make rpm
+```
 
 ### Build using Docker
 
-If you do not have a local Go toolchain, you can build entirely inside Docker
-(BuildKit is required):
+If you do not have a local Go toolchain, you can build entirely inside Docker (BuildKit is required). The following command builds all supported packages:
 
 ```bash
 $ docker build --output ./dist .
 ```
 
+#### Selecting the Packages to Build
+
+By default, packages are created for all architectures (`arm64` and `amd64`). You can select the architectires to build for by setting the `ARCH` build-time variable to the space-separated list of architectures to build for. For example, to only build packages for the `amd64` architecture run:
+
+```bash
+$ docker build --build-arg ARCH="amd64" --output ./dist .
+```
+
+The package types created by default are `deb`, `rpm`, `osx` and `msix`. To only build selected package types, set the `PACKAGE` build-time variable to the space-separated list of package types to build. The following command only builds `deb` and `rpm` packages on all architectures:
+
+```bash
+$ docker build --build-arg PACKAGE="deb rpm" --output ./dist .
+```
+
+By setting both the `ARCH` and `PACKAGE` build-time variables, you can further limit the build scope to specific packages. For example, to only build the `deb` package for the `amd64` architecture, run:
+
+```bash
+$ docker build --build-arg ARCH="amd64" --build-arg PACKAGE="deb" --output ./dist .
+```
+
 #### Installing Docker BuildKit
 
 On Docker Engine < 23.0, BuildKit must be enabled manually. On Ubuntu 22.04:
@@ -111,8 +136,6 @@ Then either prefix each `docker build` invocation with `DOCKER_BUILDKIT=1`, or
 follow the [official instructions](https://docs.docker.com/build/buildkit/#getting-started)
 to enable it globally.
 
-> For the full build guide see [doc/BUILD.md](doc/BUILD.md).
-
 ## Install
 
 ### Install manually from source