diff --git a/.travis.yml b/.travis.yml
index bdb820c0f..a61637e43 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,7 +3,7 @@ sudo: false
 language: go
 
 go:
-- 1.8.x
+- 1.9.x
 
 go_import_path: github.com/prometheus/prometheus
 
diff --git a/circle.yml b/circle.yml
index 7e09a2cbe..abd49996d 100644
--- a/circle.yml
+++ b/circle.yml
@@ -2,7 +2,7 @@ machine:
   environment:
     DOCKER_IMAGE_NAME: prom/prometheus
     QUAY_IMAGE_NAME: quay.io/prometheus/prometheus
-    DOCKER_TEST_IMAGE_NAME: quay.io/prometheus/golang-builder:1.8-base
+    DOCKER_TEST_IMAGE_NAME: quay.io/prometheus/golang-builder:1.9-base
     REPO_PATH: github.com/prometheus/prometheus
   pre:
     - sudo curl -L -o /usr/bin/docker 'https://s3-external-1.amazonaws.com/circle-downloads/docker-1.9.1-circleci'