diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 00000000..865b3f50
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1,10 @@
+# This Docker ignore file aims to optimise the build process of the interop tests.
+# The Dockerfile in ./interop-tests/Dockerfile copies a locally built binary into the container and
+# thus does not need anything else to be present in the working directory.
+*
+
+# CI will build and copy over the release binary.
+!target/release/ping
+
+# Locally, we might want to build it as `debug` binary to accelerate the build process.
+!target/debug/ping
diff --git a/.github/workflows/interop-test.yml b/.github/workflows/interop-test.yml
index bd438019..9351198b 100644
--- a/.github/workflows/interop-test.yml
+++ b/.github/workflows/interop-test.yml
@@ -24,13 +24,10 @@ jobs:
       - name: Install Protoc
         run: sudo apt-get install protobuf-compiler
       - name: Build image
-        working-directory: ./interop-tests
         run: |
           cargo build --release -p interop-tests
-          mkdir -p target/release/
-          cp ../target/release/ping target/release
-          docker build -t rust-libp2p-head .
-          docker image save -o ping-image.tar rust-libp2p-head
+          docker build -t rust-libp2p-head --build-arg=TEST_BINARY=target/release/ping . -f ./interop-tests/Dockerfile
+          docker image save -o ./interop-tests/ping-image.tar rust-libp2p-head
       - name: Upload ping versions info
         uses: actions/upload-artifact@v3
         with:
diff --git a/interop-tests/Dockerfile b/interop-tests/Dockerfile
index 0f28bb61..7197b378 100644
--- a/interop-tests/Dockerfile
+++ b/interop-tests/Dockerfile
@@ -1,4 +1,5 @@
 FROM ubuntu:22.04
-COPY target/release/ping /usr/local/bin/testplan
+ARG TEST_BINARY
+COPY $TEST_BINARY /usr/local/bin/testplan
 ENV RUST_BACKTRACE=1
 ENTRYPOINT ["testplan"]