diff --git a/.github/workflows/nix-action-8.18.yml b/.github/workflows/nix-action-8.18.yml
index 93ee66d..a2a3112 100644
--- a/.github/workflows/nix-action-8.18.yml
+++ b/.github/workflows/nix-action-8.18.yml
@@ -27,7 +27,7 @@ jobs:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v27
+      uses: cachix/install-nix-action@v30
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup ssprove
@@ -75,7 +75,7 @@ jobs:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v27
+      uses: cachix/install-nix-action@v30
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup ssprove
@@ -144,7 +144,7 @@ jobs:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v27
+      uses: cachix/install-nix-action@v30
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup ssprove
diff --git a/.github/workflows/nix-action-8.19.yml b/.github/workflows/nix-action-8.19.yml
index eead108..b3bf53a 100644
--- a/.github/workflows/nix-action-8.19.yml
+++ b/.github/workflows/nix-action-8.19.yml
@@ -27,7 +27,7 @@ jobs:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v27
+      uses: cachix/install-nix-action@v30
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup ssprove
@@ -75,7 +75,7 @@ jobs:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v27
+      uses: cachix/install-nix-action@v30
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup ssprove
@@ -144,7 +144,7 @@ jobs:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v27
+      uses: cachix/install-nix-action@v30
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup ssprove
diff --git a/.github/workflows/nix-action-8.20.yml b/.github/workflows/nix-action-8.20.yml
index b2b821b..197c724 100644
--- a/.github/workflows/nix-action-8.20.yml
+++ b/.github/workflows/nix-action-8.20.yml
@@ -27,7 +27,7 @@ jobs:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v27
+      uses: cachix/install-nix-action@v30
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup ssprove
@@ -75,7 +75,7 @@ jobs:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v27
+      uses: cachix/install-nix-action@v30
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup ssprove
@@ -144,7 +144,7 @@ jobs:
         fetch-depth: 0
         ref: ${{ env.tested_commit }}
     - name: Cachix install
-      uses: cachix/install-nix-action@v27
+      uses: cachix/install-nix-action@v30
       with:
         nix_path: nixpkgs=channel:nixpkgs-unstable
     - name: Cachix setup ssprove
diff --git a/.nix/coq-nix-toolbox.nix b/.nix/coq-nix-toolbox.nix
index 556abf8..eb2e2bb 100644
--- a/.nix/coq-nix-toolbox.nix
+++ b/.nix/coq-nix-toolbox.nix
@@ -1 +1 @@
-"b3008c9923a0f230078c0706b3427dc5fb75a9a0"
+"fb3515feec422e546de863ad0101e2a51ec9b8db"