diff --git a/.github/workflows/build_linux.yml b/.github/workflows/build_linux.yml
index b256604..78e1c59 100644
--- a/.github/workflows/build_linux.yml
+++ b/.github/workflows/build_linux.yml
@@ -136,6 +136,11 @@ jobs:
       shell: bash
       run: ./ci/github/arduino_build_sketch.sh BlockingWithNonBlocking
 
+    - name: Build Arduino sketch - ESP32Rtttl
+      working-directory: ${{env.GITHUB_WORKSPACE}}
+      shell: bash
+      run: ./ci/github/arduino_build_sketch.sh ESP32Rtttl
+
     - name: Build Arduino sketch - NonBlockingProgramMemoryRtttl
       working-directory: ${{env.GITHUB_WORKSPACE}}
       shell: bash
diff --git a/.github/workflows/build_windows.yml b/.github/workflows/build_windows.yml
index 59a58f5..603d4b0 100644
--- a/.github/workflows/build_windows.yml
+++ b/.github/workflows/build_windows.yml
@@ -128,6 +128,11 @@ jobs:
       shell: cmd
       run: call ci\github\arduino_build_sketch.bat BlockingWithNonBlocking
 
+    - name: Build Arduino sketch - ESP32Rtttl
+      working-directory: ${{env.GITHUB_WORKSPACE}}
+      shell: cmd
+      run: call ci\github\arduino_build_sketch.bat ESP32Rtttl
+
     - name: Build Arduino sketch - NonBlockingProgramMemoryRtttl
       working-directory: ${{env.GITHUB_WORKSPACE}}
       shell: cmd
diff --git a/appveyor.yml b/appveyor.yml
index c89e9a6..608f8bc 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -58,6 +58,7 @@ build_script:
 - cmd: call %APPVEYOR_BUILD_FOLDER%\ci\appveyor\arduino_build_sketch.bat BlockingProgramMemoryRtttl
 - cmd: call %APPVEYOR_BUILD_FOLDER%\ci\appveyor\arduino_build_sketch.bat BlockingRtttl
 - cmd: call %APPVEYOR_BUILD_FOLDER%\ci\appveyor\arduino_build_sketch.bat BlockingWithNonBlocking
+- cmd: call %APPVEYOR_BUILD_FOLDER%\ci\appveyor\arduino_build_sketch.bat ESP32Rtttl
 - cmd: call %APPVEYOR_BUILD_FOLDER%\ci\appveyor\arduino_build_sketch.bat NonBlockingProgramMemoryRtttl
 - cmd: call %APPVEYOR_BUILD_FOLDER%\ci\appveyor\arduino_build_sketch.bat NonBlockingRtttl
 - cmd: call %APPVEYOR_BUILD_FOLDER%\ci\appveyor\arduino_build_sketch.bat NonBlockingStopBeforeEnd