diff --git a/etc/ci/buildbot_steps.yml b/etc/ci/buildbot_steps.yml
index 6206ed3e70b2..dff02df1e77f 100644
--- a/etc/ci/buildbot_steps.yml
+++ b/etc/ci/buildbot_steps.yml
@@ -155,41 +155,51 @@ linux-nightly:
 android:
   - ./mach clean-nightlies --keep 3 --force
   - ./mach clean-cargo-cache --keep 3 --force
+  - ./etc/ci/clean_build_artifacts.sh
   - ./etc/ci/bootstrap-android-and-accept-licences.sh
   - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach build --android --dev
   - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach package --android --dev
   - bash ./etc/ci/lockfile_changed.sh
   - python ./etc/ci/check_dynamic_symbols.py
+  - ./etc/ci/clean_build_artifacts.sh
 
 android-x86:
   - ./mach clean-nightlies --keep 3 --force
   - ./mach clean-cargo-cache --keep 3 --force
+  - ./etc/ci/clean_build_artifacts.sh
   - ./etc/ci/bootstrap-android-and-accept-licences.sh
   - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach build --target i686-linux-android --release
   - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach test-android-startup --release
   - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach test-wpt-android --release /_mozilla/mozilla/DOMParser.html
   - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach test-wpt-android --release /_mozilla/mozilla/webgl/context_creation_error.html
   - bash ./etc/ci/lockfile_changed.sh
+  - ./etc/ci/clean_build_artifacts.sh
 
 android-nightly:
   - ./mach clean-nightlies --keep 3 --force
   - ./mach clean-cargo-cache --keep 3 --force
+  - ./etc/ci/clean_build_artifacts.sh
   - ./etc/ci/bootstrap-android-and-accept-licences.sh
   - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach build --android --release
   - env --unset ANDROID_NDK --unset ANDROID_SDK ./mach package --android --release
   - ./mach upload-nightly android
+  - ./etc/ci/clean_build_artifacts.sh
 
 arm32:
   - ./mach clean-nightlies --keep 3 --force
   - ./mach clean-cargo-cache --keep 3 --force
+  - ./etc/ci/clean_build_artifacts.sh
   - ./mach build --rel --target=arm-unknown-linux-gnueabihf
   - bash ./etc/ci/lockfile_changed.sh
+  - ./etc/ci/clean_build_artifacts.sh
 
 arm64:
   - ./mach clean-nightlies --keep 3 --force
   - ./mach clean-cargo-cache --keep 3 --force
+  - ./etc/ci/clean_build_artifacts.sh
   - ./mach build --rel --target=aarch64-unknown-linux-gnu
   - bash ./etc/ci/lockfile_changed.sh
+  - ./etc/ci/clean_build_artifacts.sh
 
 windows-msvc-dev:
   env: