diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 074340b..ad7a16f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -302,3 +302,75 @@ jobs:
           set: |
             t1.tags=localhost:5000/name/app:t1
             t2.tags=localhost:5000/name/app:t2
+
+  proxy-docker-config:
+    runs-on: ubuntu-latest
+    services:
+      squid-proxy:
+        image: ubuntu/squid:latest
+        ports:
+          - 3128:3128
+    steps:
+      -
+        name: Check proxy
+        run: |
+          netstat -aptn
+          curl --retry 5 --retry-all-errors --retry-delay 0 --connect-timeout 5 --proxy http://127.0.0.1:3128 -v --insecure --head https://www.google.com
+      -
+        name: Checkout
+        uses: actions/checkout@v4
+      -
+        name: Set proxy config
+        run: |
+          mkdir -p ~/.docker
+          echo '{"proxies":{"default":{"httpProxy":"http://127.0.0.1:3128","httpsProxy":"http://127.0.0.1:3128"}}}' > ~/.docker/config.json
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+        with:
+          version: ${{ inputs.buildx-version || env.BUILDX_VERSION }}
+          driver-opts: |
+            image=${{ inputs.buildkit-image || env.BUILDKIT_IMAGE }}
+            network=host
+          buildkitd-flags: --debug
+      -
+        name: Build
+        uses: ./
+        with:
+          files: |
+            ./test/config.hcl
+          targets: app-proxy
+
+  proxy-buildkitd:
+    runs-on: ubuntu-latest
+    services:
+      squid-proxy:
+        image: ubuntu/squid:latest
+        ports:
+          - 3128:3128
+    steps:
+      -
+        name: Check proxy
+        run: |
+          netstat -aptn
+          curl --retry 5 --retry-all-errors --retry-delay 0 --connect-timeout 5 --proxy http://127.0.0.1:3128 -v --insecure --head https://www.google.com
+      -
+        name: Checkout
+        uses: actions/checkout@v4
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+        with:
+          version: ${{ inputs.buildx-version || env.BUILDX_VERSION }}
+          driver-opts: |
+            image=${{ inputs.buildkit-image || env.BUILDKIT_IMAGE }}
+            network=host
+            env.http_proxy=http://127.0.0.1:3128
+            env.https_proxy=http://127.0.0.1:3128
+          buildkitd-flags: --debug
+      -
+        name: Build
+        uses: ./
+        with:
+          files: |
+            ./test/config.hcl
diff --git a/test/config.hcl b/test/config.hcl
index 3148894..3d74018 100644
--- a/test/config.hcl
+++ b/test/config.hcl
@@ -37,3 +37,8 @@ target "app-plus" {
     IAMPLUS = "true"
   }
 }
+
+target "app-proxy" {
+  inherits = ["app"]
+  dockerfile = "proxy.Dockerfile"
+}
diff --git a/test/proxy.Dockerfile b/test/proxy.Dockerfile
new file mode 100644
index 0000000..fa38863
--- /dev/null
+++ b/test/proxy.Dockerfile
@@ -0,0 +1,9 @@
+# syntax=docker/dockerfile:1
+FROM alpine
+RUN apk add --no-cache curl net-tools
+ARG HTTP_PROXY
+ARG HTTPS_PROXY
+RUN printenv HTTP_PROXY
+RUN printenv HTTPS_PROXY
+RUN netstat -aptn
+RUN curl --retry 5 --retry-all-errors --retry-delay 0 --connect-timeout 5 --proxy $HTTP_PROXY -v --insecure --head https://www.google.com