diff --git a/.github/workflows/run-tests-pebble.yml b/.github/workflows/run-tests-pebble.yml
index 2ecdc8e..151ec88 100644
--- a/.github/workflows/run-tests-pebble.yml
+++ b/.github/workflows/run-tests-pebble.yml
@@ -20,6 +20,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-alpine
+          tags: getssl-alpine
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -34,6 +43,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-bash4-0
+          tags: getssl-bash4-0
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -48,6 +66,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-bash4-2
+          tags: getssl-bash4-2
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -62,6 +89,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-bash5-0
+          tags: getssl-bash5-0
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -76,6 +112,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-centos6
+          tags: getssl-centos6
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -90,6 +135,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-centos7
+          tags: getssl-centos7
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -104,6 +158,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-centos8
+          tags: getssl-centos8
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -118,6 +181,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-debian
+          tags: getssl-debian
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -132,6 +204,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-rockylinux8
+          tags: getssl-rockylinux8
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -146,6 +227,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-ubuntu
+          tags: getssl-ubuntu
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -160,6 +250,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-ubuntu14
+          tags: getssl-ubuntu14
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -174,6 +273,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-ubuntu16
+          tags: getssl-ubuntu16
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
@@ -188,6 +296,15 @@ jobs:
       - uses: actions/checkout@v4
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-ubuntu18
+          tags: getssl-ubuntu18
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: |
           export DOCKER_BUILDKIT=1
diff --git a/.github/workflows/run-tests-staging-acmedns.yml b/.github/workflows/run-tests-staging-acmedns.yml
index 17e6810..cf5612d 100644
--- a/.github/workflows/run-tests-staging-acmedns.yml
+++ b/.github/workflows/run-tests-staging-acmedns.yml
@@ -21,6 +21,17 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-ubuntu-acmedns
+          tags: getssl-ubuntu-acmedns
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: docker compose up -d --build
       - name: Run test suite on Ubuntu against Staging using acmedns
diff --git a/.github/workflows/run-tests-staging-duckdns.yml b/.github/workflows/run-tests-staging-duckdns.yml
index a599830..a888f31 100644
--- a/.github/workflows/run-tests-staging-duckdns.yml
+++ b/.github/workflows/run-tests-staging-duckdns.yml
@@ -8,6 +8,17 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-centos7-duckdns
+          tags: getssl-centos7-duckdns
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: docker compose up -d --build
       - name: Run test suite on CentOS7 against Staging using DuckDNS
@@ -18,6 +29,17 @@ jobs:
     needs: test-centos7-duckdns
     steps:
       - uses: actions/checkout@v4
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-ubuntu-duckdns
+          tags: getssl-ubuntu-duckdns
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: docker compose up -d --build
       - name: Run test suite on Ubuntu against Staging using DuckDNS
diff --git a/.github/workflows/run-tests-staging-dynu.yml b/.github/workflows/run-tests-staging-dynu.yml
index 7d935c5..76ec8ea 100644
--- a/.github/workflows/run-tests-staging-dynu.yml
+++ b/.github/workflows/run-tests-staging-dynu.yml
@@ -8,6 +8,17 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-centos7-dynu
+          tags: getssl-centos7-dynu
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: docker compose up -d --build
       - name: Run test suite on CentOS7 against Staging using Dynu
@@ -18,6 +29,17 @@ jobs:
     needs: test-centos7-dynu
     steps:
       - uses: actions/checkout@v4
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Build test image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: test/Dockerfile-ubuntu-dynu
+          tags: getssl-ubuntu-dynu
+          load: true
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
       - name: Build the docker compose stack
         run: docker compose up -d --build
       - name: Run test suite on Ubuntu against Staging using Dynu
diff --git a/test/run-test.sh b/test/run-test.sh
index 814ec99..d9be619 100755
--- a/test/run-test.sh
+++ b/test/run-test.sh
@@ -68,7 +68,10 @@ else
   INT=""
 fi
 
-docker buildx build --load --rm -f "test/Dockerfile-$OS" -t "getssl-$OS" --cache-from=type=gha --cache-to=type=gha,mode=max .
+# Check if image already exists (built by GitHub Action), otherwise build it
+if ! docker image inspect "getssl-$OS" >/dev/null 2>&1; then
+  docker buildx build --load --rm -f "test/Dockerfile-$OS" -t "getssl-$OS" --cache-from=type=gha --cache-to=type=gha,mode=max .
+fi
 # shellcheck disable=SC2086
 docker run $INT\
   --env GETSSL_HOST=$ALIAS $STAGING \