How about now?

.travis.yml

@@ -7,6 +7,7 @@ jobs:
     nix: 2.1.3
     install:
       - nix-env -iA cachix -f https://cachix.org/api/v1/install
+      - stack --no-terminal --install-ghc build king --only-dependencies
 
     script:
       - cachix use urbit2
@@ -17,10 +18,18 @@ jobs:
 
     before_install:
       - git lfs pull
+      - sh/travis-install-stack
 
   - os: osx
     language: generic
     sudo: required
+
+    before_install:
+      - sh/travis-install-stack
+
+    install:
+      - stack --no-terminal --install-ghc build king --only-dependencies
+
     script:
       - ver="$(git rev-parse HEAD)"
       - if [ -n "${TRAVIS_COMMIT-}" ]; then ver="$TRAVIS_COMMIT"; fi
@@ -37,12 +46,6 @@ cache:
   - $HOME/.stack
   - $TRAVIS_BUILD_DIR/.stack-work
 
-before_install:
-  - sh/travis-install-stack
-
-install:
-  - stack --no-terminal --install-ghc build king --only-dependencies
-
 deploy:
   - skip_cleanup: true
     provider: gcs