diff --git a/.github/workflows/docker-action.yml b/.github/workflows/docker-action.yml
index 42d6f5e..4b83b68 100644
--- a/.github/workflows/docker-action.yml
+++ b/.github/workflows/docker-action.yml
@@ -20,6 +20,9 @@ jobs:
       matrix:
         image:
           - 'mathcomp/mathcomp-dev:coq-dev'
+          - 'mathcomp/mathcomp:2.1.0-coq-8.18'
+          - 'mathcomp/mathcomp:2.1.0-coq-8.17'
+          - 'mathcomp/mathcomp:2.1.0-coq-8.16'
           - 'mathcomp/mathcomp:2.0.0-coq-8.18'
           - 'mathcomp/mathcomp:2.0.0-coq-8.17'
           - 'mathcomp/mathcomp:2.0.0-coq-8.16'
diff --git a/.github/workflows/nix-action-8.17.yml b/.github/workflows/nix-action-8.17.yml
index 06230eb..6b977d4 100644
--- a/.github/workflows/nix-action-8.17.yml
+++ b/.github/workflows/nix-action-8.17.yml
@@ -40,8 +40,8 @@ jobs:
       name: Checking presence of CI target coq
       run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
         \ bundle \"8.17\" --argstr job \"coq\" \\\n   --dry-run 2>&1 > /dev/null)\n\
-        echo $nb_dry_run\necho ::set-output name=status::$(echo $nb_dry_run | grep\
-        \ \"built:\" | sed \"s/.*/built/\")\n"
+        echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
+        s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
       name: Building/fetching current CI target
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.17" --argstr
@@ -88,8 +88,8 @@ jobs:
       name: Checking presence of CI target mathcomp
       run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
         \ bundle \"8.17\" --argstr job \"mathcomp\" \\\n   --dry-run 2>&1 > /dev/null)\n\
-        echo $nb_dry_run\necho ::set-output name=status::$(echo $nb_dry_run | grep\
-        \ \"built:\" | sed \"s/.*/built/\")\n"
+        echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
+        s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
       name: 'Building/fetching previous CI target: coq'
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.17" --argstr
@@ -168,8 +168,8 @@ jobs:
       name: Checking presence of CI target reglang
       run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
         \ bundle \"8.17\" --argstr job \"reglang\" \\\n   --dry-run 2>&1 > /dev/null)\n\
-        echo $nb_dry_run\necho ::set-output name=status::$(echo $nb_dry_run | grep\
-        \ \"built:\" | sed \"s/.*/built/\")\n"
+        echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
+        s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
       name: 'Building/fetching previous CI target: coq'
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "8.17" --argstr
@@ -186,8 +186,10 @@ name: Nix CI for bundle 8.17
 'on':
   pull_request:
     paths:
-    - .github/workflows/**
+    - .github/workflows/nix-action-8.17.yml
   pull_request_target:
+    paths-ignore:
+    - .github/workflows/nix-action-8.17.yml
     types:
     - opened
     - synchronize
diff --git a/.github/workflows/nix-action-master.yml b/.github/workflows/nix-action-master.yml
index 8ae191b..b22092a 100644
--- a/.github/workflows/nix-action-master.yml
+++ b/.github/workflows/nix-action-master.yml
@@ -40,8 +40,8 @@ jobs:
       name: Checking presence of CI target coq
       run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
         \ bundle \"master\" --argstr job \"coq\" \\\n   --dry-run 2>&1 > /dev/null)\n\
-        echo $nb_dry_run\necho ::set-output name=status::$(echo $nb_dry_run | grep\
-        \ \"built:\" | sed \"s/.*/built/\")\n"
+        echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
+        s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
       name: Building/fetching current CI target
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "master"
@@ -88,8 +88,8 @@ jobs:
       name: Checking presence of CI target coq-elpi
       run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
         \ bundle \"master\" --argstr job \"coq-elpi\" \\\n   --dry-run 2>&1 > /dev/null)\n\
-        echo $nb_dry_run\necho ::set-output name=status::$(echo $nb_dry_run | grep\
-        \ \"built:\" | sed \"s/.*/built/\")\n"
+        echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
+        s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
       name: 'Building/fetching previous CI target: coq'
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "master"
@@ -141,8 +141,8 @@ jobs:
       name: Checking presence of CI target hierarchy-builder
       run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
         \ bundle \"master\" --argstr job \"hierarchy-builder\" \\\n   --dry-run 2>&1\
-        \ > /dev/null)\necho $nb_dry_run\necho ::set-output name=status::$(echo $nb_dry_run\
-        \ | grep \"built:\" | sed \"s/.*/built/\")\n"
+        \ > /dev/null)\necho $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"\
+        built:\" | sed \"s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
       name: 'Building/fetching previous CI target: coq'
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "master"
@@ -198,8 +198,8 @@ jobs:
       name: Checking presence of CI target mathcomp
       run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
         \ bundle \"master\" --argstr job \"mathcomp\" \\\n   --dry-run 2>&1 > /dev/null)\n\
-        echo $nb_dry_run\necho ::set-output name=status::$(echo $nb_dry_run | grep\
-        \ \"built:\" | sed \"s/.*/built/\")\n"
+        echo $nb_dry_run\necho status=$(echo $nb_dry_run | grep \"built:\" | sed \"\
+        s/.*/built/\") >> $GITHUB_OUTPUT\n"
     - if: steps.stepCheck.outputs.status == 'built'
       name: 'Building/fetching previous CI target: coq'
       run: NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link --argstr bundle "master"
@@ -278,8 +278,8 @@ jobs:
       name: Checking presence of CI target reglang
       run: "nb_dry_run=$(NIXPKGS_ALLOW_UNFREE=1 nix-build --no-out-link \\\n   --argstr\
         \ bundle \"master\" --argstr job \"reglang\" \\\n   --dry-run 2>&1 > /dev/null)\n\
-        echo $nb_dry_run\necho ::set-output name=status::$(echo $nb_dry_run | grep\
-        \ \"built:\" | sed \"s/.*/built/\")\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 "master"
@@ -296,8 +296,10 @@ name: Nix CI for bundle master
 'on':
   pull_request:
     paths:
-    - .github/workflows/**
+    - .github/workflows/nix-action-master.yml
   pull_request_target:
+    paths-ignore:
+    - .github/workflows/nix-action-master.yml
     types:
     - opened
     - synchronize
diff --git a/.nix/coq-nix-toolbox.nix b/.nix/coq-nix-toolbox.nix
index a9dbaff..40241c8 100644
--- a/.nix/coq-nix-toolbox.nix
+++ b/.nix/coq-nix-toolbox.nix
@@ -1 +1 @@
-"721d4a5e7a4db115f7576828c354d62a84d7055b"
+"4e48948fa8252a2fc755182abdd4b199f4798724"
diff --git a/README.md b/README.md
index 79b8e60..81565d9 100644
--- a/README.md
+++ b/README.md
@@ -11,8 +11,8 @@ Follow the instructions on https://github.com/coq-community/templates to regener
 [![coqdoc][coqdoc-shield]][coqdoc-link]
 [![DOI][doi-shield]][doi-link]
 
-[docker-action-shield]: https://github.com/coq-community/reglang/workflows/Docker%20CI/badge.svg?branch=master
-[docker-action-link]: https://github.com/coq-community/reglang/actions?query=workflow:"Docker%20CI"
+[docker-action-shield]: https://github.com/coq-community/reglang/actions/workflows/docker-action.yml/badge.svg?branch=master
+[docker-action-link]: https://github.com/coq-community/reglang/actions/workflows/docker-action.yml
 
 [contributing-shield]: https://img.shields.io/badge/contributions-welcome-%23f7931e.svg
 [contributing-link]: https://github.com/coq-community/manifesto/blob/master/CONTRIBUTING.md
diff --git a/coq-reglang.opam b/coq-reglang.opam
index 8470a68..b6dc3f5 100644
--- a/coq-reglang.opam
+++ b/coq-reglang.opam
@@ -18,7 +18,7 @@ decidability results and closure properties of regular languages."""
 
 build: ["dune" "build" "-p" name "-j" jobs]
 depends: [
-  "dune" {>= "2.8"}
+  "dune" {>= "3.5"}
   "coq" {>= "8.16"}
   "coq-mathcomp-ssreflect" {>= "2.0"}
   "coq-hierarchy-builder" {>= "1.4.0"}
diff --git a/dune-project b/dune-project
index 855139f..ba21c84 100644
--- a/dune-project
+++ b/dune-project
@@ -1,3 +1,3 @@
-(lang dune 2.8)
-(using coq 0.3)
+(lang dune 3.5)
+(using coq 0.6)
 (name reglang)
diff --git a/meta.yml b/meta.yml
index d214ded..c8d7307 100644
--- a/meta.yml
+++ b/meta.yml
@@ -66,6 +66,12 @@ dependencies:
 tested_coq_opam_versions:
 - version: 'coq-dev'
   repo: 'mathcomp/mathcomp-dev'
+- version: '2.1.0-coq-8.18'
+  repo: 'mathcomp/mathcomp'
+- version: '2.1.0-coq-8.17'
+  repo: 'mathcomp/mathcomp'
+- version: '2.1.0-coq-8.16'
+  repo: 'mathcomp/mathcomp'
 - version: '2.0.0-coq-8.18'
   repo: 'mathcomp/mathcomp'
 - version: '2.0.0-coq-8.17'