diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
deleted file mode 100644
index b7685264..00000000
--- a/.github/workflows/ci.yaml
+++ /dev/null
@@ -1,87 +0,0 @@
-name: "CI"
-on:
-  push:
-    branches:
-    - main
-  pull_request:
-
-jobs:
-  build-test:
-    name: "Build & test"
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v4
-      with:
-        repository: input-output-hk/quickcheck-dynamic
-        # On pull_request events, we want to check out the latest commit of the
-        # PR, which is different to github.ref (the default, which would point
-        # to a "fake merge" commit). On push events, the default is fine as it
-        # refers to the pushed commit.
-        ref: ${{ github.event.pull_request.head.sha || github.ref }}
-        # Also ensure we have all history with all tags
-        fetch-depth: 0
-
-    - name: Prepare nix
-      uses: cachix/install-nix-action@v31
-      with:
-        extra_nix_config: |
-          accept-flake-config = true
-          log-lines = 1000
-
-    - name: Github cache ~/.cabal/packages, ~/.cabal/store and dist-newstyle
-      uses: actions/cache@v4
-      with:
-        path: |
-          ~/.cabal/packages
-          ~/.cabal/store
-          dist-newstyle
-        key: |
-          cabal-${{ runner.os }}-${{ hashFiles('cabal.project', 'default.nix', 'shell.nix') }}
-        restore-keys: |
-          cabal-${{ runner.os }}-${{ hashFiles('cabal.project', 'default.nix', 'shell.nix') }}
-
-    - name: Enter nix shell
-      uses: nicknovitski/nix-develop@v1
-
-    - name: Formatting
-      run:
-        fourmolu --mode check .
-
-    - name: Build
-      run: |
-        cabal update
-        cabal build all --ghc-options=-Werror
-
-    - name: Test
-      run:
-        cabal test all
-
-    - name: Documentation (Haddock)
-      run: |
-        .github/workflows/ci-haddock.sh
-
-    - name: Upload Documentation
-      uses: actions/upload-artifact@v4
-      with:
-        name: haddocks
-        path: ./docs
-
-  documentation:
-    name: Documentation
-    needs: [build-test]
-    runs-on: ubuntu-latest
-    steps:
-    - name: Download generated documentation
-      uses: actions/download-artifact@v4
-      with:
-        name: haddocks
-        path: docs
-
-    - name: Publish Documentation
-      if: github.event_name == 'push'
-      uses: peaceiris/actions-gh-pages@v3
-      with:
-        github_token: ${{ secrets.GITHUB_TOKEN || github.token }}
-        publish_dir: docs/
-        enable_jekyll: true
-        force_orphan: true
diff --git a/.github/workflows/haskell-ci.yml b/.github/workflows/haskell-ci.yml
new file mode 100644
index 00000000..b6105b4c
--- /dev/null
+++ b/.github/workflows/haskell-ci.yml
@@ -0,0 +1,105 @@
+name: Haskell-CI
+permissions:
+  contents: read
+
+on:
+  push:
+    branches:
+      - 'main'
+  pull_request:
+    branches:
+      - 'main'
+  schedule:
+    - cron: 0 0 * * *
+  workflow_dispatch:
+    inputs:
+      nightly:
+        description: Run with the same settings as a nightly build
+        type: boolean
+        default: false
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  check-formatting:
+    name: Check formatting
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: install fourmolu
+        run: |
+          wget https://github.com/fourmolu/fourmolu/releases/download/v0.17.0.0/fourmolu-0.17.0.0-linux-x86_64
+          chmod +x fourmolu-0.17.0.0-linux-x86_64
+          mv fourmolu-0.17.0.0-linux-x86_64 fourmolu
+      - run: ./fourmolu -c .
+
+  test-with-cabal:
+    name: Haskell-CI - Linux - ${{ matrix.ghc-version }}
+
+    strategy:
+      matrix:
+        ghc-version: [latest, 9.12, "9.10", 9.8, 9.6, 9.4, 9.2, 9.0, "8.10"]
+        os: [ubuntu-latest]
+      fail-fast: false
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - name: Set NIGHTLY environment variable if the job was triggered by the scheduler
+        if: "${{ github.event_name == 'schedule'
+              || contains(github.event.pull_request.title, 'nightly')
+              || contains(github.event.pull_request.title, 'NIGHTLY')
+              || github.event_name == 'workflow_dispatch' && github.event.inputs.nightly }}"
+        run: |
+          echo "NIGHTLY=true" >> $GITHUB_ENV
+
+      - uses: actions/checkout@v4
+      - uses: haskell-actions/setup@v2
+        with:
+          ghc-version: ${{matrix.ghc-version}}
+      - uses: actions/cache/restore@v4
+        with:
+          key: ${{ matrix.os }}-${{ matrix.ghc-version }}-${{ github.sha }}
+          path: ~/.cabal/store
+          restore-keys: ${{ matrix.os }}-${{ matrix.ghc-version }}-
+      - run: cabal build all
+      - run: cabal test all
+
+      - name: Documentation (Haddock)
+        if: "${{ matrix.ghc-version == 'latest' }}"
+        run: |
+          .github/workflows/ci-haddock.sh
+
+      - name: Upload Documentation
+        if: "${{ matrix.ghc-version == 'latest' }}"
+        uses: actions/upload-artifact@v4
+        with:
+          name: haddocks
+          path: ./docs
+
+      - uses: actions/cache/save@v4
+        with:
+          key: ${{ matrix.os }}-${{ matrix.ghc-version }}-${{ github.sha }}
+          path: ~/.cabal/store
+
+  documentation:
+    name: Documentation
+    needs: [test-with-cabal]
+    runs-on: ubuntu-latest
+    steps:
+    - name: Download generated documentation
+      uses: actions/download-artifact@v4
+      with:
+        name: haddocks
+        path: docs
+
+    - name: Publish Documentation
+      if: github.event_name == 'push'
+      uses: peaceiris/actions-gh-pages@v3
+      with:
+        github_token: ${{ secrets.GITHUB_TOKEN || github.token }}
+        publish_dir: docs/
+        enable_jekyll: true
+        force_orphan: true
diff --git a/quickcheck-dynamic/src/Test/QuickCheck/DynamicLogic/Internal.hs b/quickcheck-dynamic/src/Test/QuickCheck/DynamicLogic/Internal.hs
index 0b41933e..ec01cbf7 100644
--- a/quickcheck-dynamic/src/Test/QuickCheck/DynamicLogic/Internal.hs
+++ b/quickcheck-dynamic/src/Test/QuickCheck/DynamicLogic/Internal.hs
@@ -592,9 +592,11 @@ keepTryingUntil n g p = do
 shrinkDLTest :: DynLogicModel s => DynLogic s -> DynLogicTest s -> [DynLogicTest s]
 shrinkDLTest _ (Looping _) = []
 shrinkDLTest d tc =
-  [ test | as' <- shrinkScript d (getScript tc), let pruned = pruneDLTest d as'
-                                                     test = makeTestFromPruned d pruned,
-  -- Don't shrink a non-executable test case to an executable one.
+  [ test
+  | as' <- shrinkScript d (getScript tc)
+  , let pruned = pruneDLTest d as'
+        test = makeTestFromPruned d pruned
+  , -- Don't shrink a non-executable test case to an executable one.
   case (tc, test) of
     (DLScript _, _) -> True
     (_, DLScript _) -> False
@@ -619,10 +621,10 @@ shrinkScript = shrink' initialAnnotatedState
       [TestSeqStep (unsafeCoerceVar var := act') ss | Some act'@ActionWithPolarity{} <- computeShrinkAction s act]
         ++ [ TestSeqStep step ss'
            | ss' <-
-              shrink'
-                (nextStateStep step s)
-                (stepDLStep d s step)
-                ss
+               shrink'
+                 (nextStateStep step s)
+                 (stepDLStep d s step)
+                 ss
            ]
     nonstructural _ _ TestSeqStop = []
 
diff --git a/quickcheck-dynamic/src/Test/QuickCheck/StateModel.hs b/quickcheck-dynamic/src/Test/QuickCheck/StateModel.hs
index daccbbcf..5c801da8 100644
--- a/quickcheck-dynamic/src/Test/QuickCheck/StateModel.hs
+++ b/quickcheck-dynamic/src/Test/QuickCheck/StateModel.hs
@@ -286,7 +286,8 @@ instance Show Polarity where
   show PosPolarity = "+"
   show NegPolarity = "-"
 
-data ActionWithPolarity state a = Eq (Action state a) =>
+data ActionWithPolarity state a
+  = Eq (Action state a) =>
   ActionWithPolarity
   { polarAction :: Action state a
   , polarity :: Polarity