diff --git a/.github/workflows/Nixpkgs-Linux-additional.yml b/.github/workflows/Nixpkgs-Linux-additional.yml
deleted file mode 100644
index f38a3db..0000000
--- a/.github/workflows/Nixpkgs-Linux-additional.yml
+++ /dev/null
@@ -1,66 +0,0 @@
-name: "Nixpkgs, Linux, additional"
-
-
-on:
-  # On Git changes in PR
-  pull_request:
-  # On Git changes of the master
-  push:
-    branches:
-      - master
-  schedule:
-    # Every day at 03:45
-    - cron: "45 06 * * *"
-
-
-env:
-  rev: "nixos-unstable"
-  cachixAccount: "hnix"
-  CACHIX_SIGNING_KEY: ${{ secrets.CACHIX_SIGNING_KEY }}
-  linkWithGold: "true"
-
-
-jobs:
-
-  build40:
-    name: "Nixpkgs-unstable channel, default GHC (8.8)"
-    runs-on: ubuntu-latest
-    continue-on-error: true
-    env:
-      rev: "nixpkgs-unstable"
-    steps:
-    - name: Git checkout
-      uses: actions/checkout@v2
-      with:
-        submodules: recursive
-    - name: Install Nix
-      uses: cachix/install-nix-action@v10
-    - name: Install Cachix
-      uses: cachix/cachix-action@v6
-      with:
-        name: ${{ env.cachixAccount }}
-        signingKey: '${{ secrets.CACHIX_SIGNING_KEY }}'
-    - name: Determined Nix-build
-      run: ./build.sh
-
-
-  build50:
-    name: "NixOS-unstable channel, GHC 8.6.5"
-    runs-on: ubuntu-latest
-    continue-on-error: true
-    env:
-      compiler: "ghc865"
-    steps:
-    - name: Git checkout
-      uses: actions/checkout@v2
-      with:
-        submodules: recursive
-    - name: Install Nix
-      uses: cachix/install-nix-action@v10
-    - name: Install Cachix
-      uses: cachix/cachix-action@v6
-      with:
-        name: ${{ env.cachixAccount }}
-        signingKey: '${{ secrets.CACHIX_SIGNING_KEY }}'
-    - name: Determined Nix-build
-      run: ./build.sh
diff --git a/.github/workflows/On-Release-Cabal-Linux.yml b/.github/workflows/On-Release-Cabal-Linux.yml
new file mode 100644
index 0000000..35acee6
--- /dev/null
+++ b/.github/workflows/On-Release-Cabal-Linux.yml
@@ -0,0 +1,39 @@
+name: "Release testing, Hackage, Cabal, Linux"
+
+on:
+  release:
+    # created: a draft is saved, or a release or pre-release is published without previously being saved as a draft
+    - created
+
+jobs:
+
+  build10:
+    name: GHC
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        # Since CI by default tests boundary GHCs, test middle versions of GHCs
+        ghc: [ "8.8", "8.6"]
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          submodules: recursive
+      - name: Cache of ~/.cabal/packages, ~/.cabal/store and dist-newstyle
+        uses: actions/cache@v2
+        with:
+          path: |
+            ~/.cabal/packages
+            ~/.cabal/store
+            dist-newstyle
+          key: ${{ runner.os }}-Cabal-${{ matrix.ghc }}
+      - uses: actions/setup-haskell@v1.1
+        with:
+          ghc-version: ${{ matrix.ghc }}
+      - name: Install additional system packages
+        run: sudo apt install libsodium-dev
+      #  2020-08-01: NOTE: Nix instantiate still needed for HNix tests
+      - name: Install Nix
+        uses: cachix/install-nix-action@v10
+      - run: cabal v2-configure --disable-optimization --enable-tests --enable-deterministic
+      - run: cabal v2-build
+      - run: cabal v2-test
diff --git a/.github/workflows/Nixpkgs-macOS.yml b/.github/workflows/Optional-Nix-dev-env-macOS.yml
similarity index 96%
rename from .github/workflows/Nixpkgs-macOS.yml
rename to .github/workflows/Optional-Nix-dev-env-macOS.yml
index aff6eed..c296777 100644
--- a/.github/workflows/Nixpkgs-macOS.yml
+++ b/.github/workflows/Optional-Nix-dev-env-macOS.yml
@@ -1,4 +1,4 @@
-name: "Nixpkgs, macOS"
+name: "(Optional) Nix dev env, macOS"
   # Due to macOS is a side-build to test the platform, using nixos-unstable for additional long-term stability of it
 on:
   # On Git changes in PR
diff --git a/.github/workflows/Nixpkgs-Linux-main.yml b/.github/workflows/Optional-Nix-dev-env-main.yml
similarity index 98%
rename from .github/workflows/Nixpkgs-Linux-main.yml
rename to .github/workflows/Optional-Nix-dev-env-main.yml
index 11f4ae8..41c5496 100644
--- a/.github/workflows/Nixpkgs-Linux-main.yml
+++ b/.github/workflows/Optional-Nix-dev-env-main.yml
@@ -1,4 +1,4 @@
-name: "Nixpkgs, Linux, main"
+name: "(Optional) Nix dev env, Linux, main"
 
 # When to trigger builds
 on: