diff --git a/CHANGELOG.md b/CHANGELOG.md
index fe720f12bcf3c870156516261247344535a6d407..108a0eabbd91650676615e94fed68baf9291c879 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,13 +1,11 @@
 # Python Buildpack Changelog
 
-# 140 (2018-10-X)
+# 140 (2018-10-09)
 
-Add an `OVERRIDDEN_PIPENV_VERSION` option to override the version of Pipenv
-used in the buildpack
-Upgrade the `DEFAULT_PIPENV_VERSION` to `2018.7.1`
+Add support for detecting SLUGIFY_USES_TEXT_UNIDECODE, which is required to
+install Apache Airflow version 1.10 or higher.
 
-
-# 139 (2018-10-8)
+# 139 (2018-10-08)
 
 Improvements to Python install messaging
 
diff --git a/bin/steps/pip-install b/bin/steps/pip-install
index 1589d87fbc8d30e63be9b723138e16abde123046..5de8e3db529ac27516124014ec32daf2bb6dc924 100755
--- a/bin/steps/pip-install
+++ b/bin/steps/pip-install
@@ -8,10 +8,24 @@ if [ ! "$SKIP_PIP_INSTALL" ]; then
     # Install dependencies with Pip.
     puts-step "Installing requirements with pip"
 
-    # Set PIP_EXTRA_INDEX_URL
+    # Set Pip env vars
+    # This reads certain environment variables set on the Heroku app config
+    # and makes them accessible to the pip install process.
+    #
+    # PIP_EXTRA_INDEX_URL allows for an alternate pypi URL to be used.
     if [[ -r $ENV_DIR/PIP_EXTRA_INDEX_URL ]]; then
         PIP_EXTRA_INDEX_URL="$(cat "$ENV_DIR/PIP_EXTRA_INDEX_URL")"
         export PIP_EXTRA_INDEX_URL
+        mcount "buildvar.PIP_EXTRA_INDEX_URL"
+    fi
+
+    set +e
+
+    # Set SLUGIFY_USES_TEXT_UNIDECODE, required for Airflow versions >=1.10
+    if [[ -r $ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE ]]; then
+        SLUGIFY_USES_TEXT_UNIDECODE="$(cat "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE")"
+        export SLUGIFY_USES_TEXT_UNIDECODE
+        mcount "buildvar.SLUGIFY_USES_TEXT_UNIDECODE"
     fi
 
     set +e
diff --git a/bin/steps/pipenv b/bin/steps/pipenv
index 608b9ecd7a4b20e88b226fcfdc7db88297b7e198..5e88c77134fb73fa2fbc5b94d9c153b26cc325ab 100755
--- a/bin/steps/pipenv
+++ b/bin/steps/pipenv
@@ -30,10 +30,22 @@ if [ ! "$SKIP_PIPENV_INSTALL" ]; then
         # Skip pip install, later.
         export SKIP_PIP_INSTALL=1
 
-        # Set PIP_EXTRA_INDEX_URL
+        # Set Pip env vars
+        # This reads certain environment variables set on the Heroku app config
+        # and makes them accessible to the pip install process.
+        #
+        # PIP_EXTRA_INDEX_URL allows for an alternate pypi URL to be used.
         if [[ -r $ENV_DIR/PIP_EXTRA_INDEX_URL ]]; then
             PIP_EXTRA_INDEX_URL="$(cat "$ENV_DIR/PIP_EXTRA_INDEX_URL")"
             export PIP_EXTRA_INDEX_URL
+            mcount "buildvar.PIP_EXTRA_INDEX_URL"
+        fi
+
+        # Set SLUGIFY_USES_TEXT_UNIDECODE, required for Airflow versions >=1.10
+        if [[ -r $ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE ]]; then
+            SLUGIFY_USES_TEXT_UNIDECODE="$(cat "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE")"
+            export SLUGIFY_USES_TEXT_UNIDECODE
+            mcount "buildvar.SLUGIFY_USES_TEXT_UNIDECODE"
         fi
 
         export DEFAULT_PIPENV_VERSION="2018.7.1"
diff --git a/test/fixtures/airflow/requirements.txt b/test/fixtures/airflow/requirements.txt
new file mode 100644
index 0000000000000000000000000000000000000000..f59ffb9527d3615df1b362ab1f065daf98fe1edf
--- /dev/null
+++ b/test/fixtures/airflow/requirements.txt
@@ -0,0 +1 @@
+apache-airflow==1.10
diff --git a/test/run b/test/run
index 5277176bc3f37820537cb54b00fad75a4fbccf5d..f6368161bae2719f3f75e8fa4d18febfe1fef5bd 100755
--- a/test/run
+++ b/test/run
@@ -1,5 +1,12 @@
 #!/usr/bin/env bash
 
+testAirflow() {
+  export SLUGIFY_USES_TEXT_UNIDECODE="yes"
+  compile "airflow"
+  assertCaptured "apache-airflow==1.10"
+  assertCapturedSuccess
+}
+
 testPipenv() {
   compile "pipenv"
   assertCapturedSuccess