diff --git a/codeship-services.yml b/codeship-services.yml
index ab5f69b..c5417bb 100644
--- a/codeship-services.yml
+++ b/codeship-services.yml
@@ -7,6 +7,8 @@ image_builder: &build-base
   add_docker: true
   cached: true
   working_dir: /opt/molecular-design-toolkit
+  environment: &repo
+    REPO: "docker.io/autodesk/moldesign:"
 
 
 publisher:
@@ -26,6 +28,7 @@ test_moldesign_minimal: &test-base
     args:
       baseimage: moldesign_minimal
   environment:
+    <<: *repo
     TESTENV: minimal
     PYVERSION: 3
     OPENMM_CPU_THREADS: 1
@@ -38,6 +41,7 @@ test_moldesign_minimal_py2:
     args:
       baseimage: moldesign_minimal_py2
   environment:
+    <<: *repo
     TESTENV: minimal
     PYVERSION: 2
     OPENMM_CPU_THREADS: 1
@@ -50,6 +54,7 @@ test_moldesign_complete:
     args:
       baseimage: moldesign_complete
   environment:
+    <<: *repo
     TESTENV: complete
     PYVERSION: 3
     OPENMM_CPU_THREADS: 1
@@ -62,6 +67,7 @@ test_moldesign_complete_py2:
     args:
       baseimage: moldesign_complete_py2
   environment:
+    <<: *repo
     TESTENV: complete
     PYVERSION: 2
     OPENMM_CPU_THREADS: 1
diff --git a/codeship-steps.yml b/codeship-steps.yml
index a6b8fa1..d4bfed8 100644
--- a/codeship-steps.yml
+++ b/codeship-steps.yml
@@ -1,13 +1,21 @@
+# Pull previous builds from DockerHub to use as a cache.
+# These images are tagged as [imagename]-cache
 - name: pull-cache
   service: image_builder
   command: deployment/pull-cache.sh
 
+# Build the python package to be tested (and uploaded to PyPI if this is a release)
+# The package is built in the "autodesk/moldesign:moldesign_py_build-[branch name]" image
 - name: build-sdist
   service: image_builder
-  command: docker-make moldesign_py_build
+  command: bash -c "docker-make moldesign_py_build
+            --repo ${REPO} --tag ${CI_BRANCH}
             --keep-build-tags
-            -f DockerMakefiles/DockerMake.yml --tag dev
+            -f DockerMakefiles/DockerMake.yml"
 
+# Build docker images for all test environments. They will be tagged as
+# autodesk/moldesign:[imagename]-[branchname]
+# (For the sake of parallelism, we also download other images that the tests depend on)
 - name: build-and-pull-images
   service: image_builder
   type: parallel
@@ -15,23 +23,28 @@
   - name: pull-dependent-images
     command: deployment/pull-chemdocker.sh
   - name: build_py3
-    command:
-         docker-make moldesign_minimal moldesign_complete
+    command: bash -c
+          "docker-make moldesign_minimal moldesign_complete
           -f DockerMakefiles/DockerMake.yml
-          --tag dev --keep-build-tags
-          --cache-repo moldesign --cache-tag cache
+          --repo ${REPO} --tag ${CI_BRANCH}
+           --keep-build-tags
+          --cache-repo moldesign --cache-tag cache"
   - name: build_py2
-    command:
-        docker-make moldesign_minimal_py2 moldesign_complete_py2
+    command: bash -c
+         "docker-make moldesign_minimal_py2 moldesign_complete_py2
          -f DockerMakefiles/DockerMake.yml
-         --tag dev --keep-build-tags
-         --cache-repo moldesign --cache-tag cache
+         --repo ${REPO} --tag ${CI_BRANCH}
+         --keep-build-tags
+         --cache-repo moldesign --cache-tag cache"
 
+
+# Push build artifacts to Dockerhub.
+# These are tagged as autodesk/moldesign:[imagename]-[branchame]-devbuild
 - name: push-images
   type: parallel
   steps:
     - name: push-artifacts
-      command: deployment/push.sh moldesign_minimal moldesign_py2
+      command: deployment/push.sh moldesign_minimal moldesign_py2 moldesign_py_build
                                   moldesign_complete moldesign_complete_py2
       service: publisher
     - type: serial
@@ -39,14 +52,17 @@
       steps:
         - name: build-notebook
           service: image_builder
-          command: docker-make moldesign_notebook
+          command: bash -c
+              "docker-make moldesign_notebook
               -f DockerMakefiles/DockerMake.yml
-              --tag dev --cache-repo moldesign --cache-tag cache
+              --repo ${REPO} --tag ${CI_BRANCH}
+              --cache-tag cache"
         - name: push-notebook
           service: publisher
           command: deployment/push.sh moldesign_notebook
 
 
+# Prints out internal information about the test environments
 - name: print-environments
   type: parallel
   services:
@@ -58,6 +74,7 @@
    - command: deployment/print-environment.sh
      name: env-report
 
+# Run the tests in each environment.
 - name: run-tests
   type: serial
   services:
@@ -69,6 +86,9 @@
    - command: deployment/run-ci-tests.sh
      name: testrunner
 
+# If this build is tagged with a PEP440-compliant version number AND the tests have passed,
+# upload the package to PyPI, and push the docker images to dockerhub as
+# autodesk/moldesign:[imagename]-[version-number]
 - name: publish-python
   service: publisher
   # matches tags that are valid PEP440 versions
diff --git a/deployment/README.md b/deployment/README.md
index 0602eb8..44507d8 100644
--- a/deployment/README.md
+++ b/deployment/README.md
@@ -1 +1,5 @@
-Files in this directory are for use with our Codeship CI/CD setup, and aren't generally useful outside of that context.
\ No newline at end of file
+Files in this directory are for use with our Codeship CI/CD setup,
+and aren't generally useful outside of that context.
+
+
+The build process is annotated in ../codeship-steps.yml
\ No newline at end of file
diff --git a/deployment/publish.sh b/deployment/publish.sh
index 8756aaa..b10de52 100755
--- a/deployment/publish.sh
+++ b/deployment/publish.sh
@@ -18,6 +18,16 @@ else
 fi
 
 
+# Push images
+for img in moldesign_minimal       \
+           moldesign_minimal_py2   \
+           moldesign_complete      \
+           moldesign_complete_py2  \
+           moldesign_notebook; do
+   docker push ${REPO}{$img}-${CI_BRANCH} | tee -a push.log | egrep -i 'pull|already'
+done
+
+
 # Copy build artifacts
 sdist=moldesign-${pyversion}.tar.gz
 docker run moldesign_py_build:dev -v ./tmp/dists:/hostdists  cp dist/${sdist} /hostdists
diff --git a/deployment/pull-cache.sh b/deployment/pull-cache.sh
index 737a51c..7c35b4c 100755
--- a/deployment/pull-cache.sh
+++ b/deployment/pull-cache.sh
@@ -14,7 +14,7 @@ function run-pull(){
     # pull an image. If successful, retags the image with the "cache" tag
     img=$1
     tag=$2
-    imgpath="autodesk/moldesign:${img}-${tag}"
+    imgpath="${REPO}${img}-${tag}"
 
     echocmd docker pull ${imgpath} | tee -a pull.log | egrep -i 'pull|already';
 
@@ -34,6 +34,7 @@ for img in moldesign_minimal       \
            moldesign_minimal_py2   \
            moldesign_complete      \
            moldesign_complete_py2  \
+           moldesign_py_build      \
            moldesign_notebook; do
    run-pull ${img} ${CI_BRANCH}-devbuild || run-pull ${img} master || \
    echo " --> Failed to pull cache for ${img}"
diff --git a/deployment/push.sh b/deployment/push.sh
index 53a54e4..79bbbbb 100755
--- a/deployment/push.sh
+++ b/deployment/push.sh
@@ -18,8 +18,9 @@ function echocmd() {
 docker login -u ${DOCKERHUB_USER} -p ${DOCKERHUB_PASSWORD}
 
 for img in $@; do
-    remote_img=autodesk/moldesign:${img}-${CI_BRANCH}-devbuild
+    local_img=${REPO}${img}-${CI_BRANCH}
+    remote_img=${local_img}-devbuild
 
-    echocmd docker tag ${img}:dev ${remote_img}
+    echocmd docker tag ${local_img} ${remote_img}
     echocmd docker push ${remote_img} | tee -a push.log | egrep -i 'push|already';
 done
\ No newline at end of file
diff --git a/deployment/run-ci-tests.sh b/deployment/run-ci-tests.sh
index be6d0f3..de341a1 100755
--- a/deployment/run-ci-tests.sh
+++ b/deployment/run-ci-tests.sh
@@ -1,7 +1,19 @@
 #!/usr/bin/env bash
+# Drives tests for our CI system. This looks for the following environment variables:
+# Defined by codeship
+# - CI_BRANCH
+# - CI_COMMIT_MESSAGE
+# Defined in ../codeship-services.yml
+# - TESTENV
+# - PYVERSION
 
 set -e  # fail immediately if any command fails
 
+if [ -z "${CI_BRANCH}" ]; then
+   echo "FAILURE: Variable \$CI_BRANCH not defined."
+   exit 1
+fi
+
 install_location=$(python -c "import moldesign, os; print(moldesign.__path__[0])")
 test_location=$(dirname "${install_location}")
 
@@ -19,22 +31,31 @@ function send_status_update(){
 
 function check_if_tests_should_run(){
    echo "Should I run the tests in this environment?"
-   runthem=false
 
    if [[ "${CI_COMMIT_MESSAGE}" == *"--fast-ci-tests"* && "${VERSION}" != "complete.py3" ]];  then
        echo "NO: found \"--fast-ci-tests\" flag in commit message; run complete.py3 only"
        exit 0
    fi
 
+   if [[ "${CI_BRANCH}" =~ ^(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)((a|rc|b)(0|[1-9]\d*))?$ ]]
+   then
+       echo "YES: this is a release version: \"${CI_BRANCH}\""
+       return 0
+   else  # otherwise, point to the appropriate docker image tag
+       mkdir -p ~/.moldesign
+       echo "default_version_tag: ${CI_BRANCH}" >> ~/.moldesign/moldesign.yml
+   fi
+
+
    if [ "${TESTENV}" == "complete" ]; then
-       runthem=true
        echo "YES: always run in 'complete' environment"
+       return 0
    fi
 
    case "${CI_BRANCH}" in
        master|deploy|dev)
-       runthem=true
        echo "YES: always run in branch \"${CI_BRANCH}\""
+       return 0
        ;;
    esac