diff --git a/hydra/Dockerfile b/hydra/Dockerfile
index 87b2ff6..e8aca34 100644
--- a/hydra/Dockerfile
+++ b/hydra/Dockerfile
@@ -28,6 +28,7 @@ RUN apk add -U apr-dev \
                pcre-dev \
                postgresql-dev \
                subversion-dev \
+               subversion-libs \
     && echo 'will cite' | parallel --bibtex \
     && mkdir src \
         && cd src \