diff --git a/README.rst b/README.rst
index c0ff7048..f772daaf 100644
--- a/README.rst
+++ b/README.rst
@@ -58,7 +58,7 @@ directory for source code.
 
 The images currently contain:
 
-- CPython 2.7, 3.4, 3.5 and 3.6, installed in
+- CPython 2.7, 3.4, 3.5, 3.6 and 3.7, installed in
   ``/opt/python/<python tag>-<abi tag>``. The directories are named
   after the PEP 425 tags for each environment --
   e.g. ``/opt/python/cp27-cp27mu`` contains a wide-unicode CPython 2.7
@@ -99,16 +99,18 @@ $ PLATFORM=$(uname -m) TRAVIS_COMMIT=latest ./build.sh
 
 Example
 -------
+
 An example project which builds 32- and 64-bit wheels for each Python interpreter
 version can be found here: https://github.com/pypa/python-manylinux-demo.
 
 This demonstrates how to use these docker images in conjunction with auditwheel
 to build manylinux-compatible wheels using the free `travis ci <https://travis-ci.org/>`_
-continuous integration service. 
+continuous integration service.
 
-(NB: for the 32-bit images running on a 64-bit host machine, it's necessary to run 
+(NB: for the 32-bit images running on a 64-bit host machine, it's necessary to run
 everything under the command line program `linux32`, which changes reported architecture
-in new program environment. See `this example invocation <https://github.com/pypa/python-manylinux-demo/blob/master/.travis.yml#L14>`_)
+in new program environment. See `this example invocation
+<https://github.com/pypa/python-manylinux-demo/blob/master/.travis.yml#L14>`_)
 
 The PEP itself
 --------------
diff --git a/docker/build_scripts/build.sh b/docker/build_scripts/build.sh
old mode 100644
new mode 100755
index e254bd65..219703ac
--- a/docker/build_scripts/build.sh
+++ b/docker/build_scripts/build.sh
@@ -11,7 +11,7 @@ MY_DIR=$(dirname "${BASH_SOURCE[0]}")
 # Dependencies for compiling Python that we want to remove from
 # the final image after compiling Python
 # GPG installed to verify signatures on Python source tarballs.
-PYTHON_COMPILE_DEPS="zlib-devel bzip2-devel ncurses-devel sqlite-devel readline-devel tk-devel gdbm-devel db4-devel libpcap-devel xz-devel gpg"
+PYTHON_COMPILE_DEPS="zlib-devel bzip2-devel ncurses-devel sqlite-devel readline-devel tk-devel gdbm-devel db4-devel libpcap-devel xz-devel gpg libffi-devel"
 
 # Libraries that are allowed as part of the manylinux1 profile
 MANYLINUX1_DEPS="glibc-devel libstdc++-devel glib2-devel libX11-devel libXext-devel libXrender-devel  mesa-libGL-devel libICE-devel libSM-devel ncurses-devel"
diff --git a/docker/build_scripts/build_env.sh b/docker/build_scripts/build_env.sh
index c4784c91..4cc15b98 100644
--- a/docker/build_scripts/build_env.sh
+++ b/docker/build_scripts/build_env.sh
@@ -1,7 +1,7 @@
 # source me
 
 PYTHON_DOWNLOAD_URL=https://www.python.org/ftp/python
-CPYTHON_VERSIONS="2.7.15 3.4.8 3.5.5 3.6.5"
+CPYTHON_VERSIONS="2.7.15 3.4.8 3.5.5 3.6.5 3.7.0rc1"
 
 # openssl version to build, with expected sha256 hash of .tar.gz
 # archive.
diff --git a/docker/build_scripts/build_utils.sh b/docker/build_scripts/build_utils.sh
index 379fefc7..a1f06adb 100755
--- a/docker/build_scripts/build_utils.sh
+++ b/docker/build_scripts/build_utils.sh
@@ -19,6 +19,15 @@ function lex_pyver {
 }
 
 
+function pyver_dist_dir {
+    # Echoes the dist directory name of given pyver, removing alpha/beta prerelease
+    # Thus:
+    # 3.2.1   -> 3.2.1
+    # 3.7.0b4 -> 3.7.0
+    echo $1 | awk -F "." '{printf "%d.%d.%d", $1, $2, $3}'
+}
+
+
 function do_cpython_build {
     local py_ver=$1
     check_var $py_ver
@@ -64,8 +73,9 @@ function build_cpython {
     local py_ver=$1
     check_var $py_ver
     check_var $PYTHON_DOWNLOAD_URL
-    curl -fsSLO $PYTHON_DOWNLOAD_URL/$py_ver/Python-$py_ver.tgz
-    curl -fsSLO $PYTHON_DOWNLOAD_URL/$py_ver/Python-$py_ver.tgz.asc
+    local py_dist_dir=$(pyver_dist_dir $py_ver)
+    curl -fsSLO $PYTHON_DOWNLOAD_URL/$py_dist_dir/Python-$py_ver.tgz
+    curl -fsSLO $PYTHON_DOWNLOAD_URL/$py_dist_dir/Python-$py_ver.tgz.asc
     gpg --verify Python-$py_ver.tgz.asc
     if [ $(lex_pyver $py_ver) -lt $(lex_pyver 3.3) ]; then
         do_cpython_build $py_ver ucs2