diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 69df09e9d..bab3cccb7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -61,19 +61,21 @@ jobs:
   # with the platform(s) and GHC version(s) enabled below.
   # On success, upload the binaries as a downloadable artifact.
   ci:
-
     runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        # keep synced with branch protection rules, see link above
-        plan:  
-        # the oldest supported ghc, to check backward compatibility
-        # - { ghc: "810", stack: "stack --stack-yaml=stack8.10.yaml" }
-        - { ghc: "944", stack: "stack --stack-yaml=stack9.4.yaml" }
 
-    # declare env.CONTINUE variable used below, to prevent "Context access might be invalid" warnings
+    # strategy:
+    #   fail-fast: false
+    #   matrix:
+    #     # keep synced with branch protection rules, see link above
+    #     plan:
+    #     # the oldest supported ghc, to check backward compatibility
+    #     # - { ghc: "810", stack: "stack --stack-yaml=stack8.10.yaml" }
+    #     - { ghc: "944", stack: "stack --stack-yaml=stack9.4.yaml" }
+
     env:
+      ghc:   944
+      stack: stack --stack-yaml=stack9.4.yaml
+      # declare this to prevent "Context access might be invalid" warnings below
       CONTINUE:
 
     steps:
@@ -89,12 +91,12 @@ jobs:
         GITHUB_CONTEXT: ${{ toJson(github) }}
       run: |
         echo $GITHUB_CONTEXT
-        # echo "$GITHUB_SHA"
-        # echo "$GITHUB_REF"
-        # echo "$GITHUB_HEAD_REF"
-        # echo "$GITHUB_BASE_REF"
-        # git log "$GITHUB_BASE_REF"..
-        # tools/commitlint "$GITHUB_BASE_REF"..
+      # echo "$GITHUB_SHA"
+      # echo "$GITHUB_REF"
+      # echo "$GITHUB_HEAD_REF"
+      # echo "$GITHUB_BASE_REF"
+      # git log "$GITHUB_BASE_REF"..
+      # tools/commitlint "$GITHUB_BASE_REF"..
 
     - name: Check commit messages
       # keep this step synced in all workflows which do it
@@ -155,9 +157,9 @@ jobs:
         # XXX if stack.yaml is a symlink, this fails with
         #  Error: The template is not valid. .github/workflows/push.yml (Line: 103, Col: 14): hashFiles('**.yaml') failed. 
         #  Fail to hash files under directory '/home/runner/work/hledger/hledger'
-        key: ${{ runner.os }}-stack-global-${{ matrix.plan.ghc }}-${{ hashFiles('**.yaml') }}
+        key: ${{ runner.os }}-stack-global-$ghc-${{ hashFiles('**.yaml') }}
         restore-keys: |
-             ${{ runner.os }}-stack-global-${{ matrix.plan.ghc }}
+             ${{ runner.os }}-stack-global-$ghc
       if: env.CONTINUE
 
     - name: Uncache stack-installed programs in ~/.local/bin
@@ -165,54 +167,54 @@ jobs:
       uses: actions/cache@v3
       with:
         path: ~/.local/bin
-        key: ${{ runner.os }}-stack-programs-${{ matrix.plan.ghc }}-${{ hashFiles('**.yaml') }}
+        key: ${{ runner.os }}-stack-programs-$ghc-${{ hashFiles('**.yaml') }}
         restore-keys: |
-             ${{ runner.os }}-stack-programs-${{ matrix.plan.ghc }}
+             ${{ runner.os }}-stack-programs-$ghc
       if: env.CONTINUE
 
     - name: Uncache .stack-work
       uses: actions/cache@v3
       with:
         path: .stack-work
-        key: ${{ runner.os }}-stack-work-${{ matrix.plan.ghc }}-${{ hashFiles('**.yaml') }}
+        key: ${{ runner.os }}-stack-work-$ghc-${{ hashFiles('**.yaml') }}
         restore-keys: |
-             ${{ runner.os }}-stack-work-${{ matrix.plan.ghc }}
+             ${{ runner.os }}-stack-work-$ghc
       if: env.CONTINUE
 
     - name: Uncache hledger-lib/.stack-work
       uses: actions/cache@v3
       with:
         path: hledger-lib/.stack-work
-        key: ${{ runner.os }}-hledger-lib-stack-work-${{ matrix.plan.ghc }}-${{ hashFiles('hledger-lib/package.yaml') }}
+        key: ${{ runner.os }}-hledger-lib-stack-work-$ghc-${{ hashFiles('hledger-lib/package.yaml') }}
         restore-keys: |
-             ${{ runner.os }}-hledger-lib-stack-work-${{ matrix.plan.ghc }}
+             ${{ runner.os }}-hledger-lib-stack-work-$ghc
       if: env.CONTINUE
 
     - name: Uncache hledger/.stack-work
       uses: actions/cache@v3
       with:
         path: hledger/.stack-work
-        key: ${{ runner.os }}-hledger-stack-work-${{ matrix.plan.ghc }}-${{ hashFiles('hledger/package.yaml') }}
+        key: ${{ runner.os }}-hledger-stack-work-$ghc-${{ hashFiles('hledger/package.yaml') }}
         restore-keys: |
-             ${{ runner.os }}-hledger-stack-work-${{ matrix.plan.ghc }}
+             ${{ runner.os }}-hledger-stack-work-$ghc
       if: env.CONTINUE
 
     - name: Uncache hledger-ui/.stack-work
       uses: actions/cache@v3
       with:
         path: hledger-ui/.stack-work
-        key: ${{ runner.os }}-hledger-ui-stack-work-${{ matrix.plan.ghc }}-${{ hashFiles('hledger-ui/package.yaml') }}
+        key: ${{ runner.os }}-hledger-ui-stack-work-$ghc-${{ hashFiles('hledger-ui/package.yaml') }}
         restore-keys: |
-             ${{ runner.os }}-hledger-ui-stack-work-${{ matrix.plan.ghc }}
+             ${{ runner.os }}-hledger-ui-stack-work-$ghc
       if: env.CONTINUE
 
     - name: Uncache hledger-web/.stack-work
       uses: actions/cache@v3
       with:
         path: hledger-web/.stack-work
-        key: ${{ runner.os }}-hledger-web-stack-work-${{ matrix.plan.ghc }}-${{ hashFiles('hledger-web/package.yaml') }}
+        key: ${{ runner.os }}-hledger-web-stack-work-$ghc-${{ hashFiles('hledger-web/package.yaml') }}
         restore-keys: |
-             ${{ runner.os }}-hledger-web-stack-work-${{ matrix.plan.ghc }}
+             ${{ runner.os }}-hledger-web-stack-work-$ghc
       if: env.CONTINUE
 
     # actions:
@@ -227,39 +229,21 @@ jobs:
       if: env.CONTINUE
 
     - name: Install GHC
-      env:
-        stack: ${{ matrix.plan.stack }}
       run: |
         $stack setup --install-ghc
       if: env.CONTINUE
 
     - name: Install haskell deps
-      env:
-        stack: ${{ matrix.plan.stack }}
       run: |
         $stack build --test --bench --only-dependencies --dry-run
         $stack build --test --bench --only-dependencies
       if: env.CONTINUE
 
-    # - name: Build all hledger modules warning free, optimised and minimised, run unit/doc/bench tests
-    #   env:
-    #     stack: ${{ matrix.plan.stack }}
-    #   run: |
-    #     $stack install --test --bench --force-dirty --ghc-options=-fforce-recomp --ghc-options=-Werror --ghc-options=-split-sections --no-terminal
-    #     # build quicker when tweaking ci: $stack install --ghc-options=-Werror --ghc-options=-split-sections --no-terminal
-    #     # -split-sections shrinks binaries by 30% on average here
-    #     # --pedantic --no-run-benchmarks
-    #   if: env.CONTINUE
-
     # Packages are built one at a time to fail faster on error.
     # Note: doctests won't run if using GHC 9.0, see hledger-lib/package.yaml
     # Takes ~2m on a 2023 github worker.
     - name: Build all hledger modules fast, warning free, run unit/doc/bench tests
-      env:
-        stack: ${{ matrix.plan.stack }}
       run: |
-        # These previously used --force-dirty --ghc-options--fforce-recomp for some reason ?
-        # But that built hledger-lib four times and hledger three times. Try without.
         $stack install --fast --ghc-options=-Werror  --test --bench hledger-lib
         $stack install --fast --ghc-options=-Werror  --test --bench hledger
         $stack install --fast --ghc-options=-Werror  --test --bench hledger-ui
@@ -268,8 +252,6 @@ jobs:
       if: env.CONTINUE
 
     - name: Install shelltestrunner
-      env:
-        stack: ${{ matrix.plan.stack }}
       run: |
         export PATH=~/.local/bin:$PATH
         if [[ ! -x ~/.local/bin/shelltest ]]; then $stack install shelltestrunner-1.10; fi
@@ -278,8 +260,6 @@ jobs:
 
     # Takes ~30s on a 2023 github worker.
     - name: Test functional tests (excluding addons)
-      env:
-        stack: ${{ matrix.plan.stack }}
       run: |
         export PATH=~/.local/bin:$PATH
         COLUMNS=80 $stack exec -- shelltest --execdir -j16 hledger/test -x /_ -x /addons -x ledger-compat/ledger-baseline -x ledger-compat/ledger-regress -x ledger-compat/ledger-collected