diff --git a/.drone.yml b/.drone.yml
index 85a278588..f2cde1673 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -17,6 +17,7 @@ steps:
   - export DEBIAN_FRONTEND=noninteractive
   - export TRAVIS_BRANCH=$DRONE_BRANCH
   - export TRAVIS_JOB_ID=$DRONE_BUILD_NUMBER
+  - export COVERALLS_PULL_REQUEST=$DRONE_PULL_REQUEST
   - apt-get -y update
   - apt-get -y install libboost-all-dev doxygen mkdocs graphviz zlib1g-dev gcc clang make cmake python3 python3-pip git openssl libssl-dev
   - pip3 install mkdocs-material pyyaml --no-input