diff --git a/.travis.yml b/.travis.yml
index 3e95f1b5a0..289896dd3e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -19,8 +19,7 @@ install:
   # We do this conditionally because it saves us some downloading if the
   # version is the same.
   - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then
-      curl https://repo.anaconda.com/miniconda/Miniconda3-latest-MacOSX-x86_64.sh >
-    miniconda.sh;
+      curl https://repo.anaconda.com/miniconda/Miniconda3-latest-MacOSX-x86_64.sh > miniconda.sh;
       export TRAVIS_PYTHON_VERSION="3.6";
     else
       wget https://repo.anaconda.com/miniconda/Miniconda3-latest-Linux-x86_64.sh -O miniconda.sh;
@@ -47,7 +46,7 @@ install:
   # codecov requires a more recent version of certifi, but we can't uninstall the old one
   # see https://github.com/tskit-dev/tskit/issues/366
   - pip install --ignore-installed certifi
-  - pip install -r python/requirements/development.txt
+  - HTSLIB_CONFIGURE_OPTIONS=--disable-bz2 pip install -r python/requirements/development.txt
   - pip install -e python
 
 script: