diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8c1dca2..591fcc1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -53,7 +53,7 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup MPI
       id:   setup-mpi
@@ -125,7 +125,7 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup MPICH
       id:   setup1
@@ -163,7 +163,7 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup MPICH
       id:   setup1
@@ -194,7 +194,7 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup MPICH
       id:   setup1
@@ -236,7 +236,7 @@ jobs:
     steps:
 
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     - name: Setup Intel MPI
       id:   setup1