diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index f53547682..5c976b9ca 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -6,17 +6,17 @@ on:
 
 jobs:
   nix-release:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
       - name: Check out code
-        uses: actions/checkout@v2.3.4
+        uses: actions/checkout@v3
         with:
           submodules: recursive
 
       - name: Install Nix
-        uses: cachix/install-nix-action@v14.1
+        uses: cachix/install-nix-action@v15
         with:
-          install_url: "https://releases.nixos.org/nix/nix-2.3.16/install"
+          install_url: https://releases.nixos.org/nix/nix-2.7.0/install
 
       - name: Upload release.nix
         uses: ttuegel/upload-release.nix@v1.0
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 2d312943e..2f713e605 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -6,25 +6,26 @@ jobs:
   # Run ./nix/rematerialize.sh from iele-assemble if this job fails.
   test-nix-material:
     name: 'Nix materialization'
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
     - name: Check out code
-      uses: actions/checkout@v2.3.4
+      uses: actions/checkout@v3
       with:
         submodules: recursive
 
     - name: Install Nix
-      uses: cachix/install-nix-action@v14.1
+      uses: cachix/install-nix-action@v15
       with:
         extra_nix_config: |
           substituters = http://cache.nixos.org https://hydra.iohk.io
           trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ=
-        install_url: "https://releases.nixos.org/nix/nix-2.3.16/install"
+        install_url: https://releases.nixos.org/nix/nix-2.7.0/install 
 
     - name: Install Cachix
       uses: cachix/cachix-action@v10
       with:
-        name: runtimeverification
+        name: k-framework
+        authToken: '${{ secrets.CACHIX_PUBLIC_TOKEN }}' 
         extraPullNames: kore
         skipPush: true
 
@@ -36,28 +37,30 @@ jobs:
     needs: test-nix-material
     strategy:
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-20.04, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:
     - name: Check out code
-      uses: actions/checkout@v2.3.4
+      uses: actions/checkout@v3
       with:
         submodules: recursive
 
     - name: Install Nix
-      uses: cachix/install-nix-action@v14.1
+      uses: cachix/install-nix-action@v15
       with:
         extra_nix_config: |
           substituters = http://cache.nixos.org https://hydra.iohk.io
           trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ=
-        install_url: "https://releases.nixos.org/nix/nix-2.3.16/install"
+        install_url: https://releases.nixos.org/nix/nix-2.7.0/install
 
     - name: Install Cachix
       uses: cachix/cachix-action@v10
       with:
-        name: runtimeverification
+        name: k-framework
+        authToken: '${{ secrets.CACHIX_PUBLIC_TOKEN }}'
         extraPullNames: kore
         signingKey: '${{ secrets.CACHIX_SIGNING_KEY }}'
+        skipPush: true
 
     - name: Build
       run: K_OPTS=-Xmx6G nix-build --cores 1
diff --git a/.github/workflows/update.yml b/.github/workflows/update.yml
index ff5645199..2cce12aab 100644
--- a/.github/workflows/update.yml
+++ b/.github/workflows/update.yml
@@ -7,7 +7,7 @@ on:
 jobs:
   nix:
     name: 'Nix'
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
       - id: config
         run: |
@@ -22,18 +22,18 @@ jobs:
           git config --global user.email github-actions@github.com
 
       - name: Check out code
-        uses: actions/checkout@v2.3.4
+        uses: actions/checkout@v3
         with:
           ref: ${{ steps.config.outputs.ref }}
           submodules: recursive
 
       - name: Install Nix
-        uses: cachix/install-nix-action@v14.1
+        uses: cachix/install-nix-action@v15
         with:
           extra_nix_config: |
             substituters = http://cache.nixos.org https://hydra.iohk.io
             trusted-public-keys = cache.nixos.org-1:6NCHdD59X431o0gWypbMrAURkbJ16ZPMQFGspcDShjY= hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ=
-          install_url: "https://releases.nixos.org/nix/nix-2.3.16/install"
+          install_url: https://releases.nixos.org/nix/nix-2.7.0/install
 
       - name: Materialize
         run: ./nix/rematerialize.sh