diff --git a/dvc/command/show_workflow.py b/dvc/command/show_workflow.py
index fc92695c4..c91c7bc30 100644
--- a/dvc/command/show_workflow.py
+++ b/dvc/command/show_workflow.py
@@ -1,4 +1,5 @@
 import re
+import sys
 from collections import defaultdict
 
 from dvc.logger import Logger
@@ -65,7 +66,8 @@ class CmdShowWorkflow(CmdBase):
     def branches_multimap(self):
         git_cmd  = ['git', 'show-ref', '--abbrev={}'.format(self.COMMIT_LEN)]
         lines = Executor.exec_cmd_only_success(git_cmd).split('\n')
-        items_full = map(unicode.split, lines)
+        func = unicode.split if sys.version_info[0] < 3 else str.split
+        items_full = map(func, lines)
         items = map(lambda it: (it[0], re.sub(r'^refs/heads/', '', it[1])), items_full)
 
         result = defaultdict(list)
diff --git a/dvc/data_cloud.py b/dvc/data_cloud.py
index be5374709..7e217a4a5 100644
--- a/dvc/data_cloud.py
+++ b/dvc/data_cloud.py
@@ -10,6 +10,14 @@ import filecmp
 import math
 
 from boto.s3.connection import S3Connection
+try:        
+    import httplib        
+except ImportError:       
+    # Python3 workaround for ResumableDownloadHandler.        
+    # See https://github.com/boto/boto/pull/3755.     
+    import sys        
+    import http.client as httplib     
+    sys.modules['httplib'] = httplib
 from boto.s3.resumable_download_handler import ResumableDownloadHandler
 from google.cloud import storage as gc
 
diff --git a/dvc/graph/workflow.py b/dvc/graph/workflow.py
index 56a0c68f7..192e76274 100644
--- a/dvc/graph/workflow.py
+++ b/dvc/graph/workflow.py
@@ -109,7 +109,7 @@ class Workflow(object):
 
         g = nx.DiGraph(name='DVC Workflow', directed=False)
 
-        for hash in set(self._edges.keys() + self._back_edges.keys()):
+        for hash in set(list(self._edges.keys()) + list(self._back_edges.keys())):
             commit = self._commits[hash]
 
             g.add_node(hash,
diff --git a/scripts/ci/after_script.sh b/scripts/ci/after_script.sh
index 526c5a378..6fe448d99 100644
--- a/scripts/ci/after_script.sh
+++ b/scripts/ci/after_script.sh
@@ -1,5 +1,8 @@
 #!/bin/bash
 
+set -x
+set -e
+
 if [[ "$TRAVIS_OS_NAME" == "linux" && \
       "$(python -c 'import sys; print(sys.version_info[0])')" == "2" && \
       "$TRAVIS_PULL_REQUEST" == "false" && \
diff --git a/scripts/ci/before_deploy.sh b/scripts/ci/before_deploy.sh
index 23276298e..15d2dcd5b 100644
--- a/scripts/ci/before_deploy.sh
+++ b/scripts/ci/before_deploy.sh
@@ -1,3 +1,8 @@
+#!/bin/bash
+
+set -x
+set -e
+
 if [[ "$TRAVIS_EVENT_TYPE" == "cron" ]]; then
 	git config --local user.name 'Nightly Travis Builds'
 	git config --local user.email '<>'
diff --git a/scripts/ci/before_install.sh b/scripts/ci/before_install.sh
index 69211a431..0e3380acd 100644
--- a/scripts/ci/before_install.sh
+++ b/scripts/ci/before_install.sh
@@ -1,3 +1,8 @@
+#!/bin/bash
+
+set -x
+set -e
+
 if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then
 	pyenv install $PYTHON_VER
 	pyenv global $PYTHON_VER
diff --git a/scripts/ci/before_script.sh b/scripts/ci/before_script.sh
index c664cff3d..0a7173f41 100644
--- a/scripts/ci/before_script.sh
+++ b/scripts/ci/before_script.sh
@@ -1,5 +1,8 @@
 #!/bin/bash
 
+set -x
+set -e
+
 if [[ "$TRAVIS_OS_NAME" == "linux" && \
       "$(python -c 'import sys; print(sys.version_info[0])')" == "2" && \
       "$TRAVIS_PULL_REQUEST" == "false" && \
diff --git a/scripts/ci/install.sh b/scripts/ci/install.sh
index d23a9f728..3c99b2b23 100644
--- a/scripts/ci/install.sh
+++ b/scripts/ci/install.sh
@@ -1,3 +1,9 @@
+#!/bin/bash
+
+set -x
+set -e
+
+sudo apt-get install graphviz
 pip install --upgrade pip
 pip install -r requirements.txt
 pip install -r test-requirements.txt
diff --git a/scripts/ci/script.sh b/scripts/ci/script.sh
index 827f05bd1..3b45b2614 100644
--- a/scripts/ci/script.sh
+++ b/scripts/ci/script.sh
@@ -1,3 +1,8 @@
+#!/bin/bash
+
+set -x
+set -e
+
 ./unittests.sh
 ./functests.sh