diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 17af62cb1..612302397 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -6,6 +6,10 @@ jobs:
   build:
     runs-on: ubuntu-18.04
     steps:
+    - name: Set up Python 3
+      uses: actions/setup-python@v2
+      with:
+        python-version: 3
     - name: Install dependencies
       run: |
         sudo apt-get update
@@ -18,18 +22,26 @@ jobs:
             lua5.3 \
             ninja-build \
             zlib1g-dev
-        sudo pip3 install --system sphinx
+        pip install sphinx
     - name: Clone DFHack
-      uses: actions/checkout@v1
+      uses: actions/checkout@v2
       with:
+        fetch-depth: 0  # unlimited - we need past tags
         submodules: true
     - name: Set up environment
+      id: env_setup
       run: |
-        echo export DF_VERSION="$(sh travis/get-df-version.sh)" >> "$HOME/.df-env"
-        echo export DF_FOLDER="$HOME/DF/$DF_VERSION/df_linux" >> "$HOME/.df-env"
+        DF_VERSION="$(sh travis/get-df-version.sh)"
+        echo "::set-env name=DF_VERSION::${DF_VERSION}"
+        echo "::set-output name=df_version::${DF_VERSION}"
+        echo "::set-env name=DF_FOLDER::${HOME}/DF/${DF_VERSION}/df_linux"
+    - name: Fetch DF cache
+      uses: actions/cache@v2
+      with:
+        path: ~/DF
+        key: ${{ steps.env_setup.outputs.df_version }}
     - name: Download DF
       run: |
-        source "$HOME/.df-env"
         sh travis/download-df.sh
     - name: Build docs
       run: |
@@ -41,7 +53,6 @@ jobs:
         path: docs/html
     - name: Build DFHack
       run: |
-        source "$HOME/.df-env"
         cmake \
           -S . \
           -B build-ci \
@@ -53,7 +64,6 @@ jobs:
         ninja -C build-ci install
     - name: Run tests
       run: |
-        source "$HOME/.df-env"
         export TERM=dumb
         mv "$DF_FOLDER"/dfhack.init-example "$DF_FOLDER"/dfhack.init
         script -qe -c "python travis/run-tests.py --headless --keep-status \"$DF_FOLDER\""
@@ -66,6 +76,12 @@ jobs:
       with:
         name: test-artifacts
         path: artifacts
+    - name: Clean up DF folder
+      # to prevent DFHack-generated files from ending up in the cache
+      # (download-df.sh also removes them, this is just to save cache space)
+      if: success() || failure()
+      run: |
+        rm -rf "$DF_FOLDER"
   lint:
     runs-on: ubuntu-18.04
     steps:
diff --git a/travis/download-df.sh b/travis/download-df.sh
index 834aa4da7..49dcedea7 100755
--- a/travis/download-df.sh
+++ b/travis/download-df.sh
@@ -1,8 +1,9 @@
 #!/bin/sh
 
+set -e
+
 tardest="df.tar.bz2"
 
-which md5sum && alias md5=md5sum
 selfmd5=$(openssl md5 < "$0")
 echo $selfmd5
 
@@ -28,7 +29,20 @@ if [ ! -f receipt ]; then
     patch=$(echo "$DF_VERSION" | cut -d. -f3)
     url="http://www.bay12games.com/dwarves/df_${minor}_${patch}_linux.tar.bz2"
     echo Downloading
-    wget "$url" -O "$tardest"
+    while read url; do
+        echo "Attempting download: ${url}"
+        if wget -v "$url" -O "$tardest"; then
+            break
+        fi
+    done <<URLS
+    https://www.bay12games.com/dwarves/df_${minor}_${patch}_linux.tar.bz2
+    https://files.dfhack.org/DF/0.${minor}.${patch}/df_${minor}_${patch}_linux.tar.bz2
+URLS
+    echo $tardest
+    if ! test -f "$tardest"; then
+        echo "DF failed to download: $tardest not found"
+        exit 1
+    fi
 fi
 
 rm -rf df_linux