diff --git a/.ruby-version b/.ruby-version
index 276cbf9e28..3f684d2d90 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-2.3.0
+2.3.4
diff --git a/Makefile b/Makefile
index 07d62e64ac..d38d32e05f 100644
--- a/Makefile
+++ b/Makefile
@@ -21,6 +21,7 @@ CODECGEN_EXE=$(CODECGEN_DIR)/bin/codecgen_$(shell go env GOHOSTOS)_$(shell go en
 CODECGEN_UID=0
 GET_CODECGEN_DEPS=$(shell find $(1) -maxdepth 1 -type f -name '*.go' -not -name '*_test.go' -not -name '*.codecgen.go' -not -name '*.generated.go')
 CODECGEN_TARGETS=report/report.codecgen.go render/detailed/detailed.codecgen.go
+RUNNER_EXE=tools/runner/runner
 RM=--rm
 RUN_FLAGS=-ti
 BUILD_IN_CONTAINER=true
@@ -86,7 +87,7 @@ prog/externalui/externalui.go: client/build-external/index.html
 
 ifeq ($(BUILD_IN_CONTAINER),true)
 
-$(SCOPE_EXE) $(RUNSVINIT) lint tests shell prog/staticui/staticui.go prog/externalui/externalui.go: $(SCOPE_BACKEND_BUILD_UPTODATE)
+$(SCOPE_EXE) $(RUNSVINIT) $(RUNNER_EXE) lint tests shell prog/staticui/staticui.go prog/externalui/externalui.go: $(SCOPE_BACKEND_BUILD_UPTODATE)
 	@mkdir -p $(shell pwd)/.pkg
 	$(SUDO) docker run $(RM) $(RUN_FLAGS) \
 		-v $(shell pwd):/go/src/github.com/weaveworks/scope \
@@ -98,7 +99,7 @@ $(SCOPE_EXE) $(RUNSVINIT) lint tests shell prog/staticui/staticui.go prog/extern
 
 else
 
-$(SCOPE_EXE): $(SCOPE_BACKEND_BUILD_UPTODATE)
+$(SCOPE_EXE) $(RUNNER_EXE): $(SCOPE_BACKEND_BUILD_UPTODATE)
 	time $(GO) build $(GO_BUILD_FLAGS) -o $@ ./$(@D)
 	@strings $@ | grep cgo_stub\\\.go >/dev/null || { \
 	        rm $@; \
@@ -124,7 +125,7 @@ shell: $(SCOPE_BACKEND_BUILD_UPTODATE)
 	/bin/bash
 
 tests: $(SCOPE_BACKEND_BUILD_UPTODATE) $(CODECGEN_TARGETS)
-	./tools/test -no-go-get
+	./tools/test -no-go-get -tags $(GO_BUILD_TAGS)
 
 lint: $(SCOPE_BACKEND_BUILD_UPTODATE)
 	./tools/lint
diff --git a/circle.yml b/circle.yml
index 0858da0f16..68f6ac32f9 100644
--- a/circle.yml
+++ b/circle.yml
@@ -23,31 +23,27 @@ dependencies:
     - "~/docker"
   override:
     - |
-      sudo apt-get update &&
       sudo apt-get install jq pv &&
-      sudo chmod a+wr --recursive /usr/local/go/pkg &&
       sudo chown ubuntu:ubuntu "$HOME/.bashrc.backup"
       (curl https://sdk.cloud.google.com | bash) &&
       (test -z "$SECRET_PASSWORD" || bin/setup-circleci-secrets "$SECRET_PASSWORD") &&
-      make deps &&
+      go get github.com/2opremio/trifles/wscat &&
       mkdir -p $(dirname $SRCDIR) &&
       cp -r $(pwd)/ $SRCDIR
     - "cd $SRCDIR/client; ../tools/rebuild-image weaveworks/scope-ui-build . Dockerfile package.json webpack.production.config.js .eslintrc .babelrc && touch $SRCDIR/.scope_ui_build.uptodate"
     - "cd $SRCDIR/backend; ../tools/rebuild-image weaveworks/scope-backend-build . Dockerfile build.sh && touch $SRCDIR/.scope_backend_build.uptodate"
     - test -z "$SECRET_PASSWORD" || (cd $SRCDIR/integration; ./gce.sh make_template):
         parallel: false
-    - sudo apt-get update && sudo apt-get install python-pip && sudo pip install awscli
+    - sudo pip install awscli
+    - cd $SRCDIR; make RM= CODECGEN_UID=23 all tools/runner/runner:
+        parallel: true
 
 test:
   override:
-    - cd $SRCDIR; make RM= lint:
+    - cd $SRCDIR; case $CIRCLE_NODE_INDEX in 0) make RM= lint ;; 1) make RM= RUN_FLAGS= client-test client-lint ;; esac:
         parallel: true
     - cd $SRCDIR; COVERDIR=./coverage make RM= CODECGEN_UID=23 tests:
         parallel: true
-    - cd $SRCDIR; make RM= client-test static:
-        parallel: true
-    - cd $SRCDIR; make RM= client-lint static:
-        parallel: true
     - cd $SRCDIR; rm -f prog/scope; if [ "$CIRCLE_NODE_INDEX" = "0" ]; then GOARCH=arm make GO_BUILD_INSTALL_DEPS= RM= prog/scope; else GOOS=darwin make GO_BUILD_INSTALL_DEPS= RM= prog/scope; fi:
         parallel: true
     - cd $SRCDIR; rm -f prog/scope; make RM=:
@@ -62,9 +58,10 @@ test:
   post:
     - test -z "$SECRET_PASSWORD" || (cd $SRCDIR/integration; ./gce.sh destroy):
         parallel: true
+        background: true
     - test "$CIRCLE_NODE_INDEX" != "0" || (cd $SRCDIR; ./tools/cover/gather_coverage.sh ./coverage $SRCDIR/coverage):
         parallel: true
-    - test "$CIRCLE_NODE_INDEX" != "0" || (goveralls -repotoken $COVERALLS_REPO_TOKEN -coverprofile=$SRCDIR/profile.cov -service=circleci || true):
+    - test "$CIRCLE_NODE_INDEX" != "0" || (go get github.com/mattn/goveralls && goveralls -repotoken $COVERALLS_REPO_TOKEN -coverprofile=$SRCDIR/profile.cov -service=circleci || true):
         parallel: true
     - test "$CIRCLE_NODE_INDEX" != "0" || (cd $SRCDIR; cp scope.tar $CIRCLE_ARTIFACTS):
         parallel: true
diff --git a/extras/Makefile b/extras/Makefile
index aa045b2a24..6d3797f793 100644
--- a/extras/Makefile
+++ b/extras/Makefile
@@ -13,7 +13,7 @@ $(TARGETS):
 		weaveworks/scope-backend-build -C extras $@
 else
 $(TARGETS):
-	go build -ldflags "-extldflags \"-static\"" -tags netgo -o $@ ./$(@D)
+	go build -ldflags "-extldflags \"-static\"" -tags 'netgo unsafe' -o $@ ./$(@D)
 endif
 
 test:
diff --git a/tools/test b/tools/test
index 1497e7a2ae..e8bca6b632 100755
--- a/tools/test
+++ b/tools/test
@@ -33,9 +33,13 @@ while [ $# -gt 0 ]; do
             shift 1
             ;;
         "-netgo")
-            TAGS="-tags netgo"
+            TAGS="netgo"
             shift 1
             ;;
+        "-tags")
+            TAGS="$2"
+            shift 2
+            ;;
         "-p")
             PARALLEL=true
             shift 1
@@ -51,7 +55,7 @@ while [ $# -gt 0 ]; do
     esac
 done
 
-GO_TEST_ARGS=($TAGS -cpu 4 -timeout $TIMEOUT)
+GO_TEST_ARGS=(-tags "${TAGS[@]}" -cpu 4 -timeout $TIMEOUT)
 
 if [ -n "$SLOW" ] || [ -n "$CIRCLECI" ]; then
     SLOW=true
@@ -97,7 +101,7 @@ go test -i "${GO_TEST_ARGS[@]}" "${TESTDIRS[@]}"
 run_test() {
     local dir=$1
     if [ -z "$NO_GO_GET" ]; then
-        go get -t "$TAGS" "$dir"
+        go get -t -tags "${TAGS[@]}" "$dir"
     fi
 
     local GO_TEST_ARGS_RUN=("${GO_TEST_ARGS[@]}")