diff --git a/.travis.yml b/.travis.yml
index 5e63a68..a6af62f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,7 @@
 language: go
 go:
     - "1.10"
-    - "1.11"
+    - "1.11.4" # required per: https://github.com/golang/go/issues/30446
     - "1.12"
     - "1.13"
     - tip
@@ -11,9 +11,9 @@ matrix:
         - go: master
     fast_finish: true
 
-env:
-    global:
-        - GO111MODULE=on
+cache:
+    directories:
+        - $GOPATH/pkg/mod
 
 install: true
 
diff --git a/go.mod b/go.mod
index 02ff7b7..e289c80 100644
--- a/go.mod
+++ b/go.mod
@@ -20,4 +20,4 @@ require (
 	golang.org/x/tools v0.0.0-20200213023303-cbc0cc175f84 // indirect
 )
 
-go 1.13
+go 1.10