diff --git a/.github/workflows/nix-action-8.18.yml b/.github/workflows/nix-action-8.18.yml
index 7857c76..06e272a 100644
--- a/.github/workflows/nix-action-8.18.yml
+++ b/.github/workflows/nix-action-8.18.yml
@@ -4,41 +4,41 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Determine which commit to initially checkout
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha\
-        \ }}\" >> $GITHUB_ENV\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.target_commit }}
     - name: Determine which commit to test
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{\
-        \ github.event.repository.html_url }} refs/pull/${{ github.event.number }}/merge\
-        \ | cut -f1)\n  mergeable=$(git merge --no-commit --no-ff ${{ github.event.pull_request.base.sha\
-        \ }} > /dev/null 2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n\
-        \  if [ -z \"$merge_commit\" -o \"x$mergeable\" != \"x0\" ]; then\n    echo\
-        \ \"tested_commit=${{ github.event.pull_request.head.sha }}\" >> $GITHUB_ENV\n\
-        \  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n  fi\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v20
+      uses: cachix/install-nix-action@v27
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup coq
-      uses: cachix/cachix-action@v12
+      uses: cachix/cachix-action@v15
       with:
         extraPullNames: coq-community, math-comp
         name: coq
     - id: stepCheck
       name: Checking presence of CI target coq
-      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
-        \ bundle \"8.18\" --argstr job \"coq\" \\\n   --dry-run 2>&1 > /dev/null)\n\
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.18\" --argstr job \"coq\" \\\n   --dry-run 2>&1 > /dev/null)\n
         echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
         s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
@@ -51,41 +51,41 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Determine which commit to initially checkout
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha\
-        \ }}\" >> $GITHUB_ENV\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.target_commit }}
     - name: Determine which commit to test
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{\
-        \ github.event.repository.html_url }} refs/pull/${{ github.event.number }}/merge\
-        \ | cut -f1)\n  mergeable=$(git merge --no-commit --no-ff ${{ github.event.pull_request.base.sha\
-        \ }} > /dev/null 2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n\
-        \  if [ -z \"$merge_commit\" -o \"x$mergeable\" != \"x0\" ]; then\n    echo\
-        \ \"tested_commit=${{ github.event.pull_request.head.sha }}\" >> $GITHUB_ENV\n\
-        \  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n  fi\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v20
+      uses: cachix/install-nix-action@v27
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup coq
-      uses: cachix/cachix-action@v12
+      uses: cachix/cachix-action@v15
       with:
         extraPullNames: coq-community, math-comp
         name: coq
     - id: stepCheck
       name: Checking presence of CI target mathcomp
-      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
-        \ bundle \"8.18\" --argstr job \"mathcomp\" \\\n   --dry-run 2>&1 > /dev/null)\n\
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.18\" --argstr job \"mathcomp\" \\\n   --dry-run 2>&1 > /dev/null)\n
         echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
         s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
@@ -130,51 +130,51 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Determine which commit to initially checkout
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha\
-        \ }}\" >> $GITHUB_ENV\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.target_commit }}
     - name: Determine which commit to test
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{\
-        \ github.event.repository.html_url }} refs/pull/${{ github.event.number }}/merge\
-        \ | cut -f1)\n  mergeable=$(git merge --no-commit --no-ff ${{ github.event.pull_request.base.sha\
-        \ }} > /dev/null 2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n\
-        \  if [ -z \"$merge_commit\" -o \"x$mergeable\" != \"x0\" ]; then\n    echo\
-        \ \"tested_commit=${{ github.event.pull_request.head.sha }}\" >> $GITHUB_ENV\n\
-        \  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n  fi\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v20
+      uses: cachix/install-nix-action@v27
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup coq
-      uses: cachix/cachix-action@v12
+      uses: cachix/cachix-action@v15
       with:
         extraPullNames: coq-community, math-comp
         name: coq
     - id: stepCheck
       name: Checking presence of CI target mathcomp-analysis
-      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
-        \ bundle \"8.18\" --argstr job \"mathcomp-analysis\" \\\n   --dry-run 2>&1\
-        \ > /dev/null)\necho $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"\
-        built:\" | sed \"s/.*/built/\") >> $GITHUB_OUTPUT\n"
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.18\" --argstr job \"mathcomp-analysis\" \\\n   --dry-run 2>&1 >
+        /dev/null)\necho $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\"\
+        \ | sed \"s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
       name: 'Building/fetching previous CI target: coq'
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.18" --argstr
         job "coq"
     - if: steps.stepCheck.outputs.status == 'built'
-      name: 'Building/fetching previous CI target: mathcomp-classical'
+      name: 'Building/fetching previous CI target: mathcomp-reals'
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.18" --argstr
-        job "mathcomp-classical"
+        job "mathcomp-reals"
     - if: steps.stepCheck.outputs.status == 'built'
       name: 'Building/fetching previous CI target: mathcomp-field'
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.18" --argstr
@@ -198,41 +198,41 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Determine which commit to initially checkout
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha\
-        \ }}\" >> $GITHUB_ENV\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.target_commit }}
     - name: Determine which commit to test
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{\
-        \ github.event.repository.html_url }} refs/pull/${{ github.event.number }}/merge\
-        \ | cut -f1)\n  mergeable=$(git merge --no-commit --no-ff ${{ github.event.pull_request.base.sha\
-        \ }} > /dev/null 2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n\
-        \  if [ -z \"$merge_commit\" -o \"x$mergeable\" != \"x0\" ]; then\n    echo\
-        \ \"tested_commit=${{ github.event.pull_request.head.sha }}\" >> $GITHUB_ENV\n\
-        \  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n  fi\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v20
+      uses: cachix/install-nix-action@v27
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup coq
-      uses: cachix/cachix-action@v12
+      uses: cachix/cachix-action@v15
       with:
         extraPullNames: coq-community, math-comp
         name: coq
     - id: stepCheck
       name: Checking presence of CI target ssprove
-      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
-        \ bundle \"8.18\" --argstr job \"ssprove\" \\\n   --dry-run 2>&1 > /dev/null)\n\
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.18\" --argstr job \"ssprove\" \\\n   --dry-run 2>&1 > /dev/null)\n
         echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
         s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
@@ -264,7 +264,7 @@ jobs:
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.18" --argstr
         job "ssprove"
 name: Nix CI for bundle 8.18
-'on':
+on:
   pull_request:
     paths:
     - .github/workflows/nix-action-8.18.yml
diff --git a/.github/workflows/nix-action-8.19.yml b/.github/workflows/nix-action-8.19.yml
index 36cebd7..13278b8 100644
--- a/.github/workflows/nix-action-8.19.yml
+++ b/.github/workflows/nix-action-8.19.yml
@@ -4,41 +4,41 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Determine which commit to initially checkout
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha\
-        \ }}\" >> $GITHUB_ENV\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.target_commit }}
     - name: Determine which commit to test
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{\
-        \ github.event.repository.html_url }} refs/pull/${{ github.event.number }}/merge\
-        \ | cut -f1)\n  mergeable=$(git merge --no-commit --no-ff ${{ github.event.pull_request.base.sha\
-        \ }} > /dev/null 2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n\
-        \  if [ -z \"$merge_commit\" -o \"x$mergeable\" != \"x0\" ]; then\n    echo\
-        \ \"tested_commit=${{ github.event.pull_request.head.sha }}\" >> $GITHUB_ENV\n\
-        \  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n  fi\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v20
+      uses: cachix/install-nix-action@v27
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup coq
-      uses: cachix/cachix-action@v12
+      uses: cachix/cachix-action@v15
       with:
         extraPullNames: coq-community, math-comp
         name: coq
     - id: stepCheck
       name: Checking presence of CI target coq
-      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
-        \ bundle \"8.19\" --argstr job \"coq\" \\\n   --dry-run 2>&1 > /dev/null)\n\
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.19\" --argstr job \"coq\" \\\n   --dry-run 2>&1 > /dev/null)\n
         echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
         s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
@@ -51,41 +51,41 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Determine which commit to initially checkout
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha\
-        \ }}\" >> $GITHUB_ENV\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.target_commit }}
     - name: Determine which commit to test
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{\
-        \ github.event.repository.html_url }} refs/pull/${{ github.event.number }}/merge\
-        \ | cut -f1)\n  mergeable=$(git merge --no-commit --no-ff ${{ github.event.pull_request.base.sha\
-        \ }} > /dev/null 2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n\
-        \  if [ -z \"$merge_commit\" -o \"x$mergeable\" != \"x0\" ]; then\n    echo\
-        \ \"tested_commit=${{ github.event.pull_request.head.sha }}\" >> $GITHUB_ENV\n\
-        \  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n  fi\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v20
+      uses: cachix/install-nix-action@v27
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup coq
-      uses: cachix/cachix-action@v12
+      uses: cachix/cachix-action@v15
       with:
         extraPullNames: coq-community, math-comp
         name: coq
     - id: stepCheck
       name: Checking presence of CI target mathcomp
-      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
-        \ bundle \"8.19\" --argstr job \"mathcomp\" \\\n   --dry-run 2>&1 > /dev/null)\n\
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.19\" --argstr job \"mathcomp\" \\\n   --dry-run 2>&1 > /dev/null)\n
         echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
         s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
@@ -130,51 +130,51 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Determine which commit to initially checkout
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha\
-        \ }}\" >> $GITHUB_ENV\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.target_commit }}
     - name: Determine which commit to test
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{\
-        \ github.event.repository.html_url }} refs/pull/${{ github.event.number }}/merge\
-        \ | cut -f1)\n  mergeable=$(git merge --no-commit --no-ff ${{ github.event.pull_request.base.sha\
-        \ }} > /dev/null 2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n\
-        \  if [ -z \"$merge_commit\" -o \"x$mergeable\" != \"x0\" ]; then\n    echo\
-        \ \"tested_commit=${{ github.event.pull_request.head.sha }}\" >> $GITHUB_ENV\n\
-        \  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n  fi\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v20
+      uses: cachix/install-nix-action@v27
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup coq
-      uses: cachix/cachix-action@v12
+      uses: cachix/cachix-action@v15
       with:
         extraPullNames: coq-community, math-comp
         name: coq
     - id: stepCheck
       name: Checking presence of CI target mathcomp-analysis
-      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
-        \ bundle \"8.19\" --argstr job \"mathcomp-analysis\" \\\n   --dry-run 2>&1\
-        \ > /dev/null)\necho $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"\
-        built:\" | sed \"s/.*/built/\") >> $GITHUB_OUTPUT\n"
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.19\" --argstr job \"mathcomp-analysis\" \\\n   --dry-run 2>&1 >
+        /dev/null)\necho $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\"\
+        \ | sed \"s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
       name: 'Building/fetching previous CI target: coq'
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.19" --argstr
         job "coq"
     - if: steps.stepCheck.outputs.status == 'built'
-      name: 'Building/fetching previous CI target: mathcomp-classical'
+      name: 'Building/fetching previous CI target: mathcomp-reals'
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.19" --argstr
-        job "mathcomp-classical"
+        job "mathcomp-reals"
     - if: steps.stepCheck.outputs.status == 'built'
       name: 'Building/fetching previous CI target: mathcomp-field'
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.19" --argstr
@@ -198,41 +198,41 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Determine which commit to initially checkout
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha\
-        \ }}\" >> $GITHUB_ENV\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.target_commit }}
     - name: Determine which commit to test
-      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{\
-        \ github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{\
-        \ github.event.repository.html_url }} refs/pull/${{ github.event.number }}/merge\
-        \ | cut -f1)\n  mergeable=$(git merge --no-commit --no-ff ${{ github.event.pull_request.base.sha\
-        \ }} > /dev/null 2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n\
-        \  if [ -z \"$merge_commit\" -o \"x$mergeable\" != \"x0\" ]; then\n    echo\
-        \ \"tested_commit=${{ github.event.pull_request.head.sha }}\" >> $GITHUB_ENV\n\
-        \  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n  fi\nfi\n"
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
     - name: Git checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v20
+      uses: cachix/install-nix-action@v27
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup coq
-      uses: cachix/cachix-action@v12
+      uses: cachix/cachix-action@v15
       with:
         extraPullNames: coq-community, math-comp
         name: coq
     - id: stepCheck
       name: Checking presence of CI target ssprove
-      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
-        \ bundle \"8.19\" --argstr job \"ssprove\" \\\n   --dry-run 2>&1 > /dev/null)\n\
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.19\" --argstr job \"ssprove\" \\\n   --dry-run 2>&1 > /dev/null)\n
         echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
         s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
@@ -264,7 +264,7 @@ jobs:
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.19" --argstr
         job "ssprove"
 name: Nix CI for bundle 8.19
-'on':
+on:
   pull_request:
     paths:
     - .github/workflows/nix-action-8.19.yml
diff --git a/.github/workflows/nix-action-8.20.yml b/.github/workflows/nix-action-8.20.yml
new file mode 100644
index 0000000..ee52af5
--- /dev/null
+++ b/.github/workflows/nix-action-8.20.yml
@@ -0,0 +1,281 @@
+jobs:
+  coq:
+    needs: []
+    runs-on: ubuntu-latest
+    steps:
+    - name: Determine which commit to initially checkout
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
+    - name: Git checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+        ref: ${{ env.target_commit }}
+    - name: Determine which commit to test
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
+    - name: Git checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+        ref: ${{ env.tested_commit }}
+    - name: Cachix install
+      uses: cachix/install-nix-action@v27
+      with:
+        nix_path: nixpkgs=channel:nixpkgs-unstable
+    - name: Cachix setup coq
+      uses: cachix/cachix-action@v15
+      with:
+        extraPullNames: coq-community, math-comp
+        name: coq
+    - id: stepCheck
+      name: Checking presence of CI target coq
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.20\" --argstr job \"coq\" \\\n   --dry-run 2>&1 > /dev/null)\n
+        echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
+        s/.*/built/\") >> $GITHUB_OUTPUT\n"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: Building/fetching current CI target
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "coq"
+  mathcomp:
+    needs:
+    - coq
+    runs-on: ubuntu-latest
+    steps:
+    - name: Determine which commit to initially checkout
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
+    - name: Git checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+        ref: ${{ env.target_commit }}
+    - name: Determine which commit to test
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
+    - name: Git checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+        ref: ${{ env.tested_commit }}
+    - name: Cachix install
+      uses: cachix/install-nix-action@v27
+      with:
+        nix_path: nixpkgs=channel:nixpkgs-unstable
+    - name: Cachix setup coq
+      uses: cachix/cachix-action@v15
+      with:
+        extraPullNames: coq-community, math-comp
+        name: coq
+    - id: stepCheck
+      name: Checking presence of CI target mathcomp
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.20\" --argstr job \"mathcomp\" \\\n   --dry-run 2>&1 > /dev/null)\n
+        echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
+        s/.*/built/\") >> $GITHUB_OUTPUT\n"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: coq'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "coq"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: mathcomp-ssreflect'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-ssreflect"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: mathcomp-fingroup'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-fingroup"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: mathcomp-algebra'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-algebra"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: mathcomp-solvable'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-solvable"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: mathcomp-field'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-field"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: mathcomp-character'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-character"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: hierarchy-builder'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "hierarchy-builder"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: Building/fetching current CI target
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp"
+  mathcomp-analysis:
+    needs:
+    - coq
+    runs-on: ubuntu-latest
+    steps:
+    - name: Determine which commit to initially checkout
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
+    - name: Git checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+        ref: ${{ env.target_commit }}
+    - name: Determine which commit to test
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
+    - name: Git checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+        ref: ${{ env.tested_commit }}
+    - name: Cachix install
+      uses: cachix/install-nix-action@v27
+      with:
+        nix_path: nixpkgs=channel:nixpkgs-unstable
+    - name: Cachix setup coq
+      uses: cachix/cachix-action@v15
+      with:
+        extraPullNames: coq-community, math-comp
+        name: coq
+    - id: stepCheck
+      name: Checking presence of CI target mathcomp-analysis
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.20\" --argstr job \"mathcomp-analysis\" \\\n   --dry-run 2>&1 >
+        /dev/null)\necho $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\"\
+        \ | sed \"s/.*/built/\") >> $GITHUB_OUTPUT\n"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: coq'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "coq"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: mathcomp-reals'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-reals"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: mathcomp-field'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-field"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: mathcomp-bigenough'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-bigenough"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: hierarchy-builder'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "hierarchy-builder"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: Building/fetching current CI target
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-analysis"
+  ssprove:
+    needs:
+    - coq
+    - mathcomp-analysis
+    runs-on: ubuntu-latest
+    steps:
+    - name: Determine which commit to initially checkout
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"target_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  echo \"target_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\nfi\n"
+    - name: Git checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+        ref: ${{ env.target_commit }}
+    - name: Determine which commit to test
+      run: "if [ ${{ github.event_name }} = \"push\" ]; then\n  echo \"tested_commit=${{
+        github.sha }}\" >> $GITHUB_ENV\nelse\n  merge_commit=$(git ls-remote ${{ github.event.repository.html_url
+        }} refs/pull/${{ github.event.number }}/merge | cut -f1)\n  mergeable=$(git
+        merge --no-commit --no-ff ${{ github.event.pull_request.base.sha }} > /dev/null
+        2>&1; echo $?; git merge --abort > /dev/null 2>&1 || true)\n  if [ -z \"$merge_commit\"\
+        \ -o \"x$mergeable\" != \"x0\" ]; then\n    echo \"tested_commit=${{ github.event.pull_request.head.sha
+        }}\" >> $GITHUB_ENV\n  else\n    echo \"tested_commit=$merge_commit\" >> $GITHUB_ENV\n\
+        \  fi\nfi\n"
+    - name: Git checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+        ref: ${{ env.tested_commit }}
+    - name: Cachix install
+      uses: cachix/install-nix-action@v27
+      with:
+        nix_path: nixpkgs=channel:nixpkgs-unstable
+    - name: Cachix setup coq
+      uses: cachix/cachix-action@v15
+      with:
+        extraPullNames: coq-community, math-comp
+        name: coq
+    - id: stepCheck
+      name: Checking presence of CI target ssprove
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr
+        bundle \"8.20\" --argstr job \"ssprove\" \\\n   --dry-run 2>&1 > /dev/null)\n
+        echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
+        s/.*/built/\") >> $GITHUB_OUTPUT\n"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: coq'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "coq"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: equations'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "equations"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: mathcomp-ssreflect'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-ssreflect"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: mathcomp-analysis'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "mathcomp-analysis"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: extructures'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "extructures"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: deriving'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "deriving"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: Building/fetching current CI target
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.20" --argstr
+        job "ssprove"
+name: Nix CI for bundle 8.20
+on:
+  pull_request:
+    paths:
+    - .github/workflows/nix-action-8.20.yml
+  pull_request_target:
+    paths-ignore:
+    - .github/workflows/nix-action-8.20.yml
+    types:
+    - opened
+    - synchronize
+    - reopened
+  push:
+    branches:
+    - main
+  workflow_dispatch:
diff --git a/.nix/config.nix b/.nix/config.nix
index 195296d..3b79c53 100644
--- a/.nix/config.nix
+++ b/.nix/config.nix
@@ -58,6 +58,15 @@
     mathcomp.override.version = "2.2.0";
     mathcomp-analysis.override.version = "1.0.0";
   };
+  bundles."8.20".coqPackages = {
+    coq.override.version = "8.20";
+    mathcomp.override.version = "2.2.0";
+    mathcomp-analysis.override.version = "1.2.0";
+  };
+
+  bundles."8.18".push-branches = ["main"];
+  bundles."8.19".push-branches = ["main"];
+  bundles."8.20".push-branches = ["main"];
 
   ## Cachix caches to use in CI
   ## Below we list some standard ones
diff --git a/.nix/coq-nix-toolbox.nix b/.nix/coq-nix-toolbox.nix
index c339840..556abf8 100644
--- a/.nix/coq-nix-toolbox.nix
+++ b/.nix/coq-nix-toolbox.nix
@@ -1 +1 @@
-"544d3d77a4a0f4fef30ad7825d2a8d2255abb0e3"
+"b3008c9923a0f230078c0706b3427dc5fb75a9a0"
diff --git a/.nix/nixpkgs.nix b/.nix/nixpkgs.nix
index 551bfce..0d13734 100644
--- a/.nix/nixpkgs.nix
+++ b/.nix/nixpkgs.nix
@@ -1,4 +1,4 @@
 fetchTarball {
-         url = https://github.com/NixOS/nixpkgs/archive/045a097bde2100af7301e50632a02d0425031042.tar.gz;
-         sha256 = "1gw6xkyzhc08q93dkb6p2s0c8b7vhj9nq5amwn5146ag38cp0j3l";
+         url = https://github.com/NixOS/nixpkgs/archive/470e6e641f412894086b6df2f204847bd3905f17.tar.gz;
+         sha256 = "196l018hbmykm6bg82mnzp9qdbcqjm3rhiia4qsvybxd90f1dbb3";
        }
diff --git a/theories/Crypt/package/pkg_heap.v b/theories/Crypt/package/pkg_heap.v
index 6bfa430..d8217d1 100644
--- a/theories/Crypt/package/pkg_heap.v
+++ b/theories/Crypt/package/pkg_heap.v
@@ -201,7 +201,7 @@ Proof.
     pose proof e as ep. simpl in ep.
     rewrite setmE in ep. rewrite eqxx in ep. noconf ep.
   }
-  rewrite -Heqcall. clear Heqcall.
+  try rewrite -Heqcall. clear Heqcall.
   pose proof e as ep. simpl in ep.
   rewrite setmE in ep. rewrite eqxx in ep. noconf ep.
   rewrite (cast_pointed_value_K (ℓ0.π1 ; v)).
@@ -215,7 +215,7 @@ Lemma get_set_heap_neq :
 Proof.
   intros h ℓ v ℓ' ne.
   funelim (get_heap (set_heap h ℓ v) ℓ').
-  - rewrite -Heqcall. clear Heqcall.
+  - try rewrite -Heqcall. clear Heqcall.
     pose proof e as ep. simpl in ep.
     rewrite setmE in ep.
     eapply negbTE in ne. rewrite ne in ep.
@@ -223,17 +223,17 @@ Proof.
     2:{
       rewrite -e in ep. noconf ep.
     }
-    rewrite -Heqcall. clear Heqcall.
+    try rewrite -Heqcall. clear Heqcall.
     apply cast_pointed_value_ext.
     rewrite -e in ep. noconf ep. reflexivity.
-  - rewrite -Heqcall. clear Heqcall.
+  - try rewrite -Heqcall. clear Heqcall.
     clear H. simpl in e. rewrite setmE in e.
     eapply negbTE in ne. rewrite ne in e.
     funelim (get_heap h ℓ).
     1:{
       rewrite -e in e0. noconf e0.
     }
-    rewrite -Heqcall. reflexivity.
+    try rewrite -Heqcall. reflexivity.
 Qed.
 
 Lemma set_heap_contract :
diff --git a/theories/Crypt/package/pkg_invariants.v b/theories/Crypt/package/pkg_invariants.v
index ed13bfa..c7675a9 100644
--- a/theories/Crypt/package/pkg_invariants.v
+++ b/theories/Crypt/package/pkg_invariants.v
@@ -1093,7 +1093,7 @@ Lemma lookup_hpv_l_eq :
 Proof.
   intros ℓ v l.
   funelim (lookup_hpv_l ℓ (hpv_l ℓ v :: l)).
-  - rewrite -Heqcall. rewrite cast_loc_val_K. reflexivity.
+  - try rewrite -Heqcall. rewrite cast_loc_val_K. reflexivity.
   - exfalso. pose proof e as e'. symmetry in e'. move: e' => /eqP e'.
     contradiction.
 Qed.
@@ -1106,7 +1106,7 @@ Proof.
   intros ℓ ℓ' v l hn.
   funelim (lookup_hpv_l ℓ' (hpv_l ℓ v :: l)).
   - exfalso. rewrite -e in hn. discriminate.
-  - rewrite -Heqcall. reflexivity.
+  - try rewrite -Heqcall. reflexivity.
 Qed.
 
 Lemma lookup_hpv_r_eq :
@@ -1115,7 +1115,7 @@ Lemma lookup_hpv_r_eq :
 Proof.
   intros ℓ v l.
   funelim (lookup_hpv_r ℓ (hpv_r ℓ v :: l)).
-  - rewrite -Heqcall. rewrite cast_loc_val_K. reflexivity.
+  - try rewrite -Heqcall. rewrite cast_loc_val_K. reflexivity.
   - exfalso. pose proof e as e'. symmetry in e'. move: e' => /eqP e'.
     contradiction.
 Qed.
@@ -1128,7 +1128,7 @@ Proof.
   intros ℓ ℓ' v l hn.
   funelim (lookup_hpv_r ℓ' (hpv_r ℓ v :: l)).
   - exfalso. rewrite -e in hn. discriminate.
-  - rewrite -Heqcall. reflexivity.
+  - try rewrite -Heqcall. reflexivity.
 Qed.
 
 Lemma lookup_hpv_l_spec :
@@ -1143,7 +1143,7 @@ Proof.
   - simpl in *.
     destruct update_heaps eqn:e1. noconf e.
     eauto.
-  - rewrite -Heqcall in hl. noconf hl.
+  - try rewrite -Heqcall in hl. noconf hl.
     simpl in e0.
     destruct update_heaps eqn:e1. noconf e0.
     pose proof e as e'.
@@ -1153,7 +1153,7 @@ Proof.
   - simpl in e0.
     destruct update_heaps eqn:e1. noconf e0.
     rewrite get_set_heap_neq. 2:{ rewrite -e. auto. }
-    rewrite -Heqcall in hl. eauto.
+    try rewrite -Heqcall in hl. eauto.
 Qed.
 
 Lemma lookup_hpv_r_spec :
@@ -1168,7 +1168,7 @@ Proof.
   - simpl in *.
     destruct update_heaps eqn:e1. noconf e.
     eauto.
-  - rewrite -Heqcall in hl. noconf hl.
+  - try rewrite -Heqcall in hl. noconf hl.
     simpl in e0.
     destruct update_heaps eqn:e1. noconf e0.
     pose proof e as e'.
@@ -1178,7 +1178,7 @@ Proof.
   - simpl in e0.
     destruct update_heaps eqn:e1. noconf e0.
     rewrite get_set_heap_neq. 2:{ rewrite -e. auto. }
-    rewrite -Heqcall in hl. eauto.
+    try rewrite -Heqcall in hl. eauto.
 Qed.
 
 Lemma lookup_hpv_spec :
@@ -1205,11 +1205,11 @@ Proof.
   - simpl in *.
     destruct update_heaps eqn:e1. noconf e.
     eauto.
-  - rewrite -Heqcall in hl. noconf hl.
+  - try rewrite -Heqcall in hl. noconf hl.
   - simpl in e0.
     destruct update_heaps eqn:e1. noconf e0.
     rewrite get_set_heap_neq. 2:{ rewrite -e. auto. }
-    rewrite -Heqcall in hl. eauto.
+    try rewrite -Heqcall in hl. eauto.
 Qed.
 
 Lemma lookup_hpv_r_None_spec :
@@ -1224,11 +1224,11 @@ Proof.
   - simpl in *.
     destruct update_heaps eqn:e1. noconf e.
     eauto.
-  - rewrite -Heqcall in hl. noconf hl.
+  - try rewrite -Heqcall in hl. noconf hl.
   - simpl in e0.
     destruct update_heaps eqn:e1. noconf e0.
     rewrite get_set_heap_neq. 2:{ rewrite -e. auto. }
-    rewrite -Heqcall in hl. eauto.
+    try rewrite -Heqcall in hl. eauto.
 Qed.
 
 Lemma lookup_hpv_None_spec :
diff --git a/theories/Crypt/package/pkg_lookup.v b/theories/Crypt/package/pkg_lookup.v
index 3238860..7fc9010 100644
--- a/theories/Crypt/package/pkg_lookup.v
+++ b/theories/Crypt/package/pkg_lookup.v
@@ -91,7 +91,7 @@ Proof.
   intros L I E p hp o ho arg f e.
   funelim (get_raw_package_op p hp o ho arg).
   2:{ rewrite <- e1 in e. discriminate. }
-  rewrite <- Heqcall. cbn. rewrite <- e1 in e.
+  try rewrite <- Heqcall. cbn. rewrite <- e1 in e.
   noconf e. reflexivity.
 Qed.
 
@@ -361,4 +361,4 @@ Proof.
   unfold get_op_default.
   eapply lookup_op_spec_inv in e. rewrite e.
   reflexivity.
-Qed.
\ No newline at end of file
+Qed.
diff --git a/theories/Mon/SpecificationMonads.v b/theories/Mon/SpecificationMonads.v
index 0fd5112..56b97c2 100644
--- a/theories/Mon/SpecificationMonads.v
+++ b/theories/Mon/SpecificationMonads.v
@@ -52,7 +52,7 @@ Section MonotoneContinuationsMonad.
   Proof.
     constructor ; cbv.
     - auto with crelations.
-    - eauto using PreOrder_Transitive.
+    - pose proof PreOrder_Transitive; eauto.
   Qed.
 
   Program Definition MonoCont : OrderedMonad :=
@@ -835,4 +835,3 @@ Section WpSpRightKanExtension.
    Qed.
 ---------------------------end of forgotten section*)
 End WpSpRightKanExtension.
-