Tweak Dockerfile and add workflow for building remotely

.devcontainer/Dockerfile

@@ -1,105 +1,92 @@
-FROM debian:bookworm-slim as base
+FROM debian:bookworm-slim
 
-ENV LANG C.UTF-8
-
-ARG GHC_VERSION=9.6.3
+ARG GHC_VERSION=9.6.5
 ARG STACK_VERSION=recommended
 ARG STACK_RESOLVER=nightly
 ARG CABAL_VERSION=recommended
 ARG HLS_VERSION=recommended
-ARG LLVM_VERSION=17
 
-ENV USERNAME=vscode \
+ENV LANG=C.UTF-8 \
+    USERNAME=devcontainer \
     USER_UID=1000 \
     USER_GID=1000 \
     DEBIAN_FRONTEND=noninteractive \
+    BOOTSTRAP_HASKELL_NONINTERACTIVE=yes \
+    BOOTSTRAP_HASKELL_NO_UPGRADE=yes \
     GHC_VERSION=${GHC_VERSION} \
     STACK_VERSION=${STACK_VERSION} \
     STACK_RESOLVER=${STACK_RESOLVER} \
     CABAL_VERSION=${CABAL_VERSION} \
-    HLS_VERSION=${HLS_VERSION} \
-    LLVM_VERSION=${LLVM_VERSION}
+    HLS_VERSION=${HLS_VERSION}
 
 RUN ulimit -n 8192
-
-RUN VERSION_CODENAME=$(grep VERSION_CODENAME /etc/os-release | cut -d'=' -f2) && \
-    apt-get update && \
-    apt-get install -y --no-install-recommends software-properties-common wget && \
-    # I don't know why, nor do I have any mental capacity to figure it out,
-    # but we need to add the repository twice, otherwise it doesn't work (repo isn't being added)
-    add-apt-repository -y -s -n "deb http://apt.llvm.org/${VERSION_CODENAME}/ llvm-toolchain-${VERSION_CODENAME}-${LLVM_VERSION} main" && \
-    add-apt-repository -y -s -n "deb http://apt.llvm.org/${VERSION_CODENAME}/ llvm-toolchain-${VERSION_CODENAME}-${LLVM_VERSION} main" && \
-    wget -qO- https://apt.llvm.org/llvm-snapshot.gpg.key | tee /etc/apt/trusted.gpg.d/apt.llvm.org.asc && \
-    apt-get update && \
-    apt-get install -y --no-install-recommends apt-utils bash build-essential ca-certificates curl gcc git gnupg libffi-dev libffi8 libgmp-dev libgmp-dev libgmp10 libicu-dev libncurses-dev libncurses5 libnuma1 libnuma-dev libtinfo5 lsb-release make procps sudo xz-utils z3 zlib1g-dev clang-$LLVM_VERSION lldb-$LLVM_VERSION lld-$LLVM_VERSION clangd-$LLVM_VERSION
-
+RUN apt-get update --yes && \
+    apt-get install --yes --no-install-recommends software-properties-common wget && \
+    rm -rf /var/lib/apt/lists/*
+RUN apt-get update --yes && \
+    apt-get install --yes --no-install-recommends \
+        bash \
+        build-essential \
+        curl \
+        git \
+        libffi-dev \
+        libffi8 \
+        libgmp-dev \
+        libgmp10 \
+        libncurses-dev \
+        libncurses5 \
+        libtinfo5 \
+        sudo \
+        zlib1g-dev && \
+    rm -rf /var/lib/apt/lists/*
 RUN groupadd --gid ${USER_GID} ${USERNAME} && \
     useradd -ms /bin/bash -K MAIL_DIR=/dev/null --uid ${USER_UID} --gid ${USER_GID} -m ${USERNAME} && \
     echo ${USERNAME} ALL=\(root\) NOPASSWD:ALL > /etc/sudoers.d/${USERNAME} && \
     chmod 0440 /etc/sudoers.d/${USERNAME}
 
 USER ${USER_UID}:${USER_GID}
 WORKDIR /home/${USERNAME}
-ENV PATH="/home/${USERNAME}/.local/bin:/home/${USERNAME}/.cabal/bin:/home/${USERNAME}/.ghcup/bin:$PATH"
 
+# Add GHCUp and Cabal to the PATH
+ENV PATH="/home/${USERNAME}/.local/bin:/home/${USERNAME}/.cabal/bin:/home/${USERNAME}/.ghcup/bin:$PATH"
 RUN echo "export PATH=${PATH}" >> /home/${USERNAME}/.profile
 
-ENV BOOTSTRAP_HASKELL_NONINTERACTIVE=yes \
-    BOOTSTRAP_HASKELL_NO_UPGRADE=yes
-
-FROM base as tooling
-
+# Download and install GHCUp
 RUN curl --proto '=https' --tlsv1.2 -sSf https://get-ghcup.haskell.org | sh
 
-# Set the GHC version.
+# Download and install GHC and tooling
 RUN ghcup install ghc ${GHC_VERSION} --set
-
-# Install cabal-iinstall
 RUN ghcup install cabal ${CABAL_VERSION} --set
+RUN ghcup install stack ${STACK_VERSION} --set
+RUN ghcup install hls ${HLS_VERSION} --set
 
-# Update Cabal.
+# Configure Cabal
 RUN cabal update && cabal new-install cabal-install
-
-# Configure cabal
 RUN cabal user-config update -f && \
     sed -i 's/-- ghc-options:/ghc-options: -haddock/g' ~/.cabal/config
 
-# Install stack
-RUN ghcup install stack ${STACK_VERSION} --set
-
-# Set system-ghc, install-ghc and resolver for stack.
+# Configure Stack
 RUN ((stack ghc -- --version 2>/dev/null) || true) && \
-    # Set global defaults for stack.
     stack config --system-ghc set system-ghc true --global && \
     stack config --system-ghc set install-ghc false --global && \
     stack config --system-ghc set resolver ${STACK_RESOLVER}
-
-# Set global custom defaults for stack.
 RUN printf "ghc-options:\n  \"\$everything\": -haddock\n" >> /home/${USERNAME}/.stack/config.yaml
 
-# Install hls
-RUN ghcup install hls ${HLS_VERSION} --set
-
-FROM tooling as packages
-
-# Install global packages.
-# Versions are pinned, since we don't want to accidentally break anything (by always installing latest).
-RUN cabal install --haddock-hoogle --minimize-conflict-set \
-    fsnotify-0.4.1.0 \
-    haskell-dap-0.0.16.0 \
-    ghci-dap-0.0.22.0 \
-    haskell-debug-adapter-0.0.39.0 \
-    hlint-3.6.1 \
-    apply-refact-0.14.0.0 \
-    retrie-1.2.2 \
-    hoogle-5.0.18.3 \
-    ormolu-0.7.2.0
-
-FROM packages as hoogle
-
-# Generate hoogle db
+# Install useful dependencies
+RUN cabal update && \
+    cabal install --haddock-hoogle --minimize-conflict-set \
+        fsnotify-0.4.1.0 \
+        haskell-dap-0.0.16.0 \
+        ghci-dap-0.0.22.0 \
+        haskell-debug-adapter-0.0.39.0 \
+        hlint-3.6.1 \
+        apply-refact-0.14.0.0 \
+        retrie-1.2.2 \
+        hoogle-5.0.18.3 \
+        ormolu-0.7.2.0
+
+# Download local Hoogle database
 RUN hoogle generate --download --haskell
 
 ENV DEBIAN_FRONTEND=dialog
-
 ENTRYPOINT ["/bin/bash"]

.devcontainer/devcontainer.json

@@ -1,20 +1,8 @@
 {
   "name": "DevContainer for Haskell (GHC, Stack, Cabal, HIE, LSP, DAP, etc.)",
-  "remoteUser": "vscode",
+  "remoteUser": "devcontainer",
   "runArgs": [],
-  "build": {
-    "args": {
-      "USERNAME": "vscode",
-      "GHC_VERSION": "9.6.3",
-      "STACK_VERSION": "recommended",
-      "STACK_RESOLVER": "nightly",
-      "CABAL_VERSION": "recommended",
-      "HLS_VERSION": "recommended",
-      "LLVM_VERSION": "17"
-    },
-    "context": "..",
-    "dockerfile": "Dockerfile"
-  },
+  "image": "ghcr.io/marijnvanwezel/haskell-dev-env",
   "customizations": {
     "vscode": {
       "extensions": [

.github/workflows/build.yaml

@@ -0,0 +1,55 @@
+name: Build development container
+
+on:
+  push:
+    paths:
+      - '.devcontainer/Dockerfile'
+
+jobs:
+  build:
+    runs-on: ubuntu-22.04
+    timeout-minutes: 60
+
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - context: ./.devcontainer
+            file: Dockerfile
+            image: ghcr.io/marijnvanwezel/haskell-dev-env
+
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11
+
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@9ec57ed1fcdbf14dcef7dfbe97b2010124a938b7
+        with:
+          images: ${{ matrix.image }}
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@65b78e6e13532edd9afa3aa52ac7964289d1a9c1
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@2b51285047da1547ffb1b2203d8be4c0af6b1f20
+
+      - name: Build and push image
+        uses: docker/build-push-action@f2a1d5e99d037542a71f64918e516c093c6f3fc4
+        with:
+          context: ${{ matrix.context }}
+          file: ${{ matrix.file }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          push: true
+          # https://github.com/moby/buildkit#github-actions-cache-experimental
+          cache-from: type=gha
+          cache-to: type=gha,mode=max

.vscode/launch.json

@@ -1,7 +1,6 @@
 {
     "version": "0.2.0",
     "configurations": [
-
         {
             "type": "ghc",
             "request": "launch",