diff --git a/.github/workflows/nix-action-coq-master.yml b/.github/workflows/nix-action-coq-master.yml
index ddf8fb0102..aa0c11ff41 100644
--- a/.github/workflows/nix-action-coq-master.yml
+++ b/.github/workflows/nix-action-coq-master.yml
@@ -356,58 +356,6 @@ jobs:
       name: Building/fetching current CI target
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "coq-master"
         --argstr job "StructTact"
-  UniMath:
-    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@v3
-      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@v3
-      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-community
-      uses: cachix/cachix-action@v15
-      with:
-        authToken: ${{ secrets.CACHIX_AUTH_TOKEN }}
-        extraPullNames: coq, math-comp
-        name: coq-community
-    - id: stepCheck
-      name: Checking presence of CI target UniMath
-      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
-        \ bundle \"coq-master\" --argstr job \"UniMath\" \\\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 "coq-master"
-        --argstr job "coq"
-    - if: steps.stepCheck.outputs.status == 'built'
-      name: Building/fetching current CI target
-      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "coq-master"
-        --argstr job "UniMath"
   Verdi:
     needs:
     - coq
@@ -4180,6 +4128,63 @@ jobs:
       name: Building/fetching current CI target
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "coq-master"
         --argstr job "parsec"
+  perennial:
+    needs:
+    - coq
+    - stdlib
+    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@v3
+      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@v3
+      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-community
+      uses: cachix/cachix-action@v15
+      with:
+        authToken: ${{ secrets.CACHIX_AUTH_TOKEN }}
+        extraPullNames: coq, math-comp
+        name: coq-community
+    - id: stepCheck
+      name: Checking presence of CI target perennial
+      run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
+        \ bundle \"coq-master\" --argstr job \"perennial\" \\\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 "coq-master"
+        --argstr job "coq"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: 'Building/fetching previous CI target: stdlib'
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "coq-master"
+        --argstr job "stdlib"
+    - if: steps.stepCheck.outputs.status == 'built'
+      name: Building/fetching current CI target
+      run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "coq-master"
+        --argstr job "perennial"
   relation-algebra:
     needs:
     - coq
diff --git a/.nix/config.nix b/.nix/config.nix
index 8f27a7488f..c6b46a9a0f 100644
--- a/.nix/config.nix
+++ b/.nix/config.nix
@@ -115,7 +115,7 @@ with builtins; with (import <nixpkgs> {}).lib;
       # "coq-hammer" -> overlay
       # "flocq" -> overlay
       # "coq-performance-tests" -> overlay
-      # "coq-tools" -> overlay
+      # TODO coq-tools -> Docker
       "coquelicot"
       # "compcert" -> overlay
       # "vst" -> overlay
@@ -137,7 +137,7 @@ with builtins; with (import <nixpkgs> {}).lib;
       # "coq-elpi" -> overlay
       "hierarchy-builder"
       # "engine bench" -> overlay
-      # TODO fcsl_pcm -> not ported to MC 2, to remove
+      # TODO fcsl_pcm -> wait for MC 2 port
       # "coq-ext-lib" -> overlay
       # "simple-io" -> overlay
       # "QuickChick" -> overlay
@@ -161,7 +161,7 @@ with builtins; with (import <nixpkgs> {}).lib;
       "VerdiRaft"
       # TODO argosy -> Docker
       # "atbr" -> overlay
-      # TODO perennial -> Docker
+      # "perennial" -> overlay
       # "sf" -> overlay
       "deriving"
       # "category-theory" -> overlay
@@ -228,6 +228,7 @@ with builtins; with (import <nixpkgs> {}).lib;
       engine-bench.override.version = "proux01:split_stdlib";
       coq-performance-tests.override.version = "proux01:split_stdlib";
       coq-tools.override.version = "proux01:split_stdlib";
+      perennial.override.version = "proux01:split_stdlib";
     };
   in {
     "coq-master".coqPackages = common-bundles // {
diff --git a/.nix/coq-overlays/perennial/default.nix b/.nix/coq-overlays/perennial/default.nix
new file mode 100644
index 0000000000..660ff3fd49
--- /dev/null
+++ b/.nix/coq-overlays/perennial/default.nix
@@ -0,0 +1,21 @@
+{ lib, mkCoqDerivation, coq, stdlib, version ? null }:
+
+let
+  fetcher = { domain, owner, repo, rev, sha256 ? null, ...}:
+    fetchGit {
+      url = "https://${domain}/${owner}/${repo}";
+      ref = rev;
+      submodules = true;
+    };
+in
+
+mkCoqDerivation {
+  pname = "perennial";
+  owner = "mit-pdos";
+  inherit version fetcher;
+  defaultVersion = null;  # no released version
+
+  propagatedBuildInputs = [ stdlib ];
+
+  buildFlags = [ "TIMED=false" "lite" ];
+}