diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index c05c0de12b2efc592936ecb20872a16b09153273..41fe74d8548769e86d742d818cff208ca1baff05 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,6 +1,6 @@
 before_script:
   - ls -F
-  - apt-get update -qq && apt-get install -y wget bzip2 git make gcc gcc-multilib time
+  - apt-get update -qq && apt-get install -y wget bzip2 git make gcc gcc-multilib time bc
   - wget -nv https://common-lisp.net/project/cmucl/downloads/snapshots/2017/04/cmucl-2017-04-x86-linux.tar.bz2
   - wget -nv https://common-lisp.net/project/cmucl/downloads/snapshots/2017/04/cmucl-2017-04-x86-linux.extra.tar.bz2
   - mkdir snapshot