diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index b7ab016..40ae941 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -12,7 +12,7 @@ jobs:
         os: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v2.3.4
     - run: yarn install --frozen-lockfile
     - run: yarn build
     - name: Install Nix
@@ -31,7 +31,7 @@ jobs:
         os: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v2.3.4
     - run: yarn install --frozen-lockfile
     - run: yarn build
     - name: Install Nix
@@ -47,7 +47,7 @@ jobs:
         os: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v2.3.4
     - run: yarn install --frozen-lockfile
     - run: yarn build
     - name: Install Nix
@@ -65,16 +65,14 @@ jobs:
         os: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:
-    - uses: actions/checkout@v2
-      with:
-        # Nix Flakes doesn't work on shallow clones
-        fetch-depth: 0
+    - uses: actions/checkout@v2.3.4
     - run: yarn install --frozen-lockfile
     - run: yarn build
     - name: Install Nix
       uses: ./
       with:
-        install_url: https://github.com/numtide/nix-flakes-installer/releases/download/nix-2.4pre20201221_9fab14a/install
+        install_url: https://nixos-nix-install-tests.cachix.org/serve/lb41az54kzk6j12p81br4bczary7m145/install
+        install_options: '--tarball-url-prefix https://nixos-nix-install-tests.cachix.org/serve'
         extra_nix_config: |
           experimental-features = nix-command flakes
     - run: nix flake show github:NixOS/nixpkgs
@@ -92,6 +90,6 @@ jobs:
       uses: ./
       with: 
         nix_path: nixpkgs=channel:nixos-20.03
-        install_url: https://nix-ci.cachix.org/serve/lb41az54kzk6j12p81br4bczary7m145/install
-        install_options: '--tarball-url-prefix https://nix-ci.cachix.org/serve'
+        install_url: https://nixos-nix-install-tests.cachix.org/serve/lb41az54kzk6j12p81br4bczary7m145/install
+        install_options: '--tarball-url-prefix https://nixos-nix-install-tests.cachix.org/serve'
     - run: nix-build test.nix