diff --git a/.github/workflows/codespace.yml b/.github/workflows/codespace.yml
deleted file mode 100644
index f9a39b68..00000000
--- a/.github/workflows/codespace.yml
+++ /dev/null
@@ -1,56 +0,0 @@
-name: Build and push GitHub Codespace images
-
-on:
-  push:
-    branches:
-      - main
-  workflow_dispatch:
-
-env:
-  IMAGE_NAME: input-output-hk/devx-devcontainer
-  REGISTRY: ghcr.io
-  DEFAULT_TAG: latest
-
-jobs:
-  build_and_push:
-    permissions:
-      packages: write
-    runs-on: ubuntu-latest
-    # We want a GitHub Codespace image for each combination of devx developer shell option.
-    # But, since the purpose of GitHub Codespace is to serve a complete development environment,
-    # the user is likely to always expect HLS (I don't see the point otherwise).
-    # Therefore, it doesn't seem useful to build an image on the `-minimal` flavor (without HLS),
-    # or the `-static` one (especially since the latter currently requires `-minimal` to work).
-    # Likely, we consider using `-iog` as the default and do not generate other images.
-    # Then the user choices left would be between native, `-windows` or `-js` target platforms,
-    # and the GHC version (currently `ghc8107` and `ghc962`).
-    strategy:
-      matrix:
-        platform: ['x86_64-linux', 'aarch64-linux']
-        target-platform: ['', '-windows', '-js']
-        compiler-nix-name: ['ghc8107','ghc962']
-        minimal: [false]
-        iog: [true]
-    steps:
-    - name: Checkout repository
-      uses: actions/checkout@v3
-
-    - name: Log in to the Container registry
-      uses: docker/login-action@v2.1.0
-      with:
-        registry: ${{ env.REGISTRY }}
-        username: ${{ github.actor }}
-        password: ${{ secrets.GITHUB_TOKEN }}
-
-    - name: Build and push Docker image
-      uses: docker/build-push-action@v4
-      with:
-        context: .
-        push: true
-        tags: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ matrix.platform }}.${{ matrix.compiler-nix-name }}${{ matrix.target-platform }}-iog
-        build-args: |
-          PLATFORM=${{ matrix.platform }}
-          TARGET_PLATFORM=${{ matrix.target-platform }}
-          COMPILER_NIX_NAME=${{ matrix.compiler-nix-name }}
-          MINIMAL=${{ matrix.minimal }}
-          IOG=${{ matrix.iog }}
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 362e81fa..073532fc 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -11,7 +11,41 @@ env:
   IMAGE_NAME: ${{ github.repository }}
 
 jobs:
-  build:
+  wait-for-hydra-eval:
+    env:
+      HYDRA_JOB: ci/eval
+      GH_TOKEN: ${{ github.token }}
+    name: "Wait for hydra status"
+    runs-on: ubuntu-latest
+    steps:
+    - name: Get specific check run status
+      run: |
+        # start with a random sleep to prevent hitting the api too hard.
+        while true; do
+          # For GitHub Apps
+          # conclusion=$(gh api repos/$GITHUB_REPOSITORY/commits/$GITHUB_SHA/status --jq '.check_runs[] | select(.name == "ci/hydra-build:$DEV_SHELL") | .conclusion')
+          # For GitHub Statuses; we need --paginate because there are so many statuses
+          echo "Querying: gh api repos/$GITHUB_REPOSITORY/commits/$GITHUB_SHA/status --paginate --jq '.statuses[] | select(.context == \"$HYDRA_JOB\") | .state'"
+          conclusion=$(gh api "repos/$GITHUB_REPOSITORY/commits/$GITHUB_SHA/status" --paginate --jq ".statuses[] | select(.context == \"$HYDRA_JOB\") | .state")
+          case "$conclusion" in
+            success)
+              echo "$HYDRA_JOB succeeded"
+              exit 0;;
+            failure)
+              echo "$HYDRA_JOB failed"
+              exit 1;;
+            *)
+              echo "conclusion is: '$conclusion'"
+              gh api "repos/$GITHUB_REPOSITORY/commits/$GITHUB_SHA/status" --paginate --jq '.statuses[] | .state+"\t"+.context'|sort
+              WAIT=$((30 + RANDOM % 30))
+            echo "$HYDRA_JOB pending. Waiting ${WAIT}s..."
+            sleep $WAIT;;
+          esac
+        done
+
+  upload:
+    needs: wait-for-hydra-eval
+    name: Container Upload
     strategy:
       fail-fast: false
       matrix:
@@ -66,39 +100,10 @@ jobs:
           - target-platform: "-js"
             platform: x86_64-darwin
             variant: ""
-
-    runs-on: ubuntu-latest
-    permissions:
-      contents: read
-      packages: write
-    steps:
-      - name: Install Nix with good defaults
-        uses: cachix/install-nix-action@v20
-        with:
-          extra_nix_config: |
-            trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ= loony-tools:pr9m4BkM/5/eSTZlkQyRt57Jz7OMBxNSUiMC4FkcNfk=
-            substituters = https://cache.iog.io/ https://cache.zw3rk.com/ https://cache.nixos.org/
-          nix_path: nixpkgs=channel:nixos-unstable
-      - name: Checkout repository
-        uses: actions/checkout@v3
-      - name: Log in to the Container registry
-        uses: docker/login-action@v2.1.0
-        with:
-          registry: ${{ env.REGISTRY }}
-          username: ${{ github.actor }}
-          password: ${{ secrets.GITHUB_TOKEN }}
-      - name: Work around issue fetching cabal revision files
-        run: |
-          # This will cause the revised `.cabal` files used whan building alex
-          # for building GHC to be fetched using the `x86_64-linux` `.drv` for `fetchurl`.
-          # Later when we want the non `x86_64-linux` version later it will find the
-          # fixed output of the derivation is already in the `/nix/store` and will
-          # not try to fetch it using the platform we do not have a builder for.
-          if [[ "${{ matrix.platform }}" != "x86_64-linux" && "${{ matrix.target-platform }}" = "-js" ]]; then
-            nix build ".#hydraJobs.x86_64-linux.${{ matrix.compiler-nix-name }}-js-minimal" --show-trace
-          fi
-      - name: Compute and upload closure and developer environment to ghcr.io
-        env:
-          NIX_STORE_SECRET_KEY: ${{ secrets.SECRET_KEY }}
-          DEV_SHELL: ${{ matrix.platform }}.${{ matrix.compiler-nix-name }}${{ matrix.target-platform }}${{ matrix.variant }}${{ matrix.iog }}-env
-        run: ./extra/ghcr-upload.sh
+    uses: ./.github/workflows/wait-and-upload.yml
+    with:
+      platform: ${{ matrix.platform }}
+      target-platform: ${{ matrix.target-platform }}
+      compiler-nix-name: ${{ matrix.compiler-nix-name }}
+      minimal: ${{ matrix.variant == '-minimal' }}
+      iog: ${{ matrix.iog == '-iog' }}
\ No newline at end of file
diff --git a/.github/workflows/wait-and-upload.yml b/.github/workflows/wait-and-upload.yml
new file mode 100644
index 00000000..3dc5c72e
--- /dev/null
+++ b/.github/workflows/wait-and-upload.yml
@@ -0,0 +1,139 @@
+name: Wait and Upload
+
+on:
+  workflow_call:
+    inputs:
+      platform:
+        required: true
+        description: 'build platform'
+        type: string
+      target-platform:
+        required: true
+        description: 'target platform'
+        type: string
+      compiler-nix-name:
+        required: true
+        description: 'compiler name in nix format. e.g. ghc8107'
+        type: string
+      minimal:
+        description: 'without hls, hlint, ...'
+        type: boolean
+        default: true
+      iog:
+        description: 'without iog libs: libsodium, libsecp256k1, libblst, ...'
+        type: boolean
+        default: false
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+  DEV_SHELL: ${{ inputs.platform }}.${{ inputs.compiler-nix-name }}${{ inputs.target-platform }}${{ inputs.minimal && '-minimal' || '' }}${{ inputs.iog && '-iog' || ''}}-env
+  DEFAULT_TAG: latest
+  GH_TOKEN: ${{ github.token }}
+
+jobs:
+  wait-for-hydra:
+    name: "Wait for hydra status"
+    runs-on: ubuntu-latest
+    steps:
+    - name: Get specific check run status
+      run: |
+        # start with a random sleep to prevent hitting the api too hard.
+        while true; do
+          # For GitHub Apps
+          # conclusion=$(gh api repos/$GITHUB_REPOSITORY/commits/$GITHUB_SHA/status --jq '.check_runs[] | select(.name == "ci/hydra-build:$DEV_SHELL") | .conclusion')
+          # For GitHub Statuses; we need --paginate because there are so many statuses
+          echo "Querying: gh api repos/$GITHUB_REPOSITORY/commits/$GITHUB_SHA/status --paginate --jq '.statuses[] | select(.context == \"ci/hydra-build:$DEV_SHELL\") | .state'"
+          conclusion=$(gh api "repos/$GITHUB_REPOSITORY/commits/$GITHUB_SHA/status" --paginate --jq ".statuses[] | select(.context == \"ci/hydra-build:$DEV_SHELL\") | .state")
+          case "$conclusion" in
+            success)
+              echo "ci/hydra-build:$DEV_SHELL succeeded"
+              exit 0;;
+            failure)
+              echo "ci/hydra-build:$DEV_SHELL failed"
+              exit 1;;
+            *)
+              echo "conclusion is: '$conclusion'"
+              gh api repos/$GITHUB_REPOSITORY/commits/$GITHUB_SHA/status --paginate --jq '.statuses[] | .state+"\t"+.context'|sort
+              WAIT=$((180 + RANDOM % 180))
+              echo "ci/hydra-build:$DEV_SHELL pending. Waiting ${WAIT}s..."
+              sleep $WAIT;;
+          esac
+        done
+
+  ghcr-upload:
+    needs: wait-for-hydra
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+    steps:
+      - name: Install Nix with good defaults
+        uses: cachix/install-nix-action@v20
+        with:
+          extra_nix_config: |
+            trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ= loony-tools:pr9m4BkM/5/eSTZlkQyRt57Jz7OMBxNSUiMC4FkcNfk=
+            substituters = https://cache.iog.io/ https://cache.zw3rk.com/ https://cache.nixos.org/
+          nix_path: nixpkgs=channel:nixos-unstable
+      - name: Checkout repository
+        uses: actions/checkout@v3
+      - name: Log in to the Container registry
+        uses: docker/login-action@v2.1.0
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Work around issue fetching cabal revision files
+        run: |
+          # This will cause the revised `.cabal` files used whan building alex
+          # for building GHC to be fetched using the `x86_64-linux` `.drv` for `fetchurl`.
+          # Later when we want the non `x86_64-linux` version later it will find the
+          # fixed output of the derivation is already in the `/nix/store` and will
+          # not try to fetch it using the platform we do not have a builder for.
+          if [[ "${{ inputs.platform }}" != "x86_64-linux" && "${{ inputs.target-platform }}" = "-js" ]]; then
+            nix build ".#hydraJobs.x86_64-linux.${{ inputs.compiler-nix-name }}-js-minimal" --show-trace
+          fi
+      - name: Compute and upload closure and developer environment to ghcr.io
+        env:
+          NIX_STORE_SECRET_KEY: ${{ secrets.SECRET_KEY }}
+        run: ./extra/ghcr-upload.sh
+
+  codespace-upload:
+    env:
+      IMAGE_NAME: input-output-hk/devx-devcontainer
+    needs: ghcr-upload
+    permissions:
+      packages: write
+    runs-on: ubuntu-latest
+    # We want a GitHub Codespace image for each combination of devx developer shell option.
+    # But, since the purpose of GitHub Codespace is to serve a complete development environment,
+    # the user is likely to always expect HLS (I don't see the point otherwise).
+    # Therefore, it doesn't seem useful to build an image on the `-minimal` flavor (without HLS),
+    # or the `-static` one (especially since the latter currently requires `-minimal` to work).
+    # Likely, we consider using `-iog` as the default and do not generate other images.
+    # Then the user choices left would be between native, `-windows` or `-js` target platforms,
+    # and the GHC version (currently `ghc8107` and `ghc962`).
+    if: ${{ contains(fromJSON('["x86_64-linux", "aarch64-linux"]'), inputs.platform) && contains(fromJson('["","-windows","-js"]'), inputs.target-platform) && contains(fromJson('["ghc8107","ghc962"]'), inputs.compiler-nix-name) && !inputs.minimal && inputs.iog }}
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@v2.1.0
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v4
+        with:
+          context: .
+          push: true
+          tags: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ inputs.platform }}.${{ inputs.compiler-nix-name }}${{ inputs.target-platform }}-iog
+          build-args: |
+            PLATFORM=${{ inputs.platform }}
+            TARGET_PLATFORM=${{ inputs.target-platform }}
+            COMPILER_NIX_NAME=${{ inputs.compiler-nix-name }}
+            MINIMAL=${{ inputs.minimal }}
+            IOG=${{ inputs.iog }}