diff --git a/.test-coverage b/.test-coverage
index 6293cb2..c6bd28b 100755
--- a/.test-coverage
+++ b/.test-coverage
@@ -1,6 +1,12 @@
 #!/bin/bash
 # Issue:  https://github.com/mattn/goveralls/issues/20
 # Source: https://github.com/uber/go-torch/blob/63da5d33a225c195fea84610e2456d5f722f3963/.test-cover.sh
+CI=$1
+echo "run for $CI"
+
+if [ "$CI" == "circle-ci" ]; then
+  cd ${GOPATH}/src/github.com/${CIRCLE_PROJECT_USERNAME}/${CIRCLE_PROJECT_REPONAME}
+fi
 
 echo "mode: count" > profile.cov
 FAIL=0
@@ -20,7 +26,7 @@ done
 
 # Failures have incomplete results, so don't send
 if [ "$FAIL" -eq 0 ]; then
-  goveralls -service=travis-ci -v -coverprofile=profile.cov
+  goveralls -service=$CI -v -coverprofile=profile.cov
   bash <(curl -s https://codecov.io/bash) -t $CODECOV_TOKEN -f profile.cov
 fi
 
diff --git a/.travis.yml b/.travis.yml
index e601586..4b8901b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,5 +7,5 @@ install:
   - go get github.com/mattn/goveralls
   - go get golang.org/x/tools/cmd/cover
 script:
-  - ./.test-coverage
+  - ./.test-coverage travis-ci
   - go install github.com/FreifunkBremen/yanic
diff --git a/README.md b/README.md
index faad9e7..dd1b3a6 100644
--- a/README.md
+++ b/README.md
@@ -9,6 +9,7 @@ Yet another node info collector
 ```
 
 [![Build Status](https://travis-ci.org/FreifunkBremen/yanic.svg?branch=master)](https://travis-ci.org/FreifunkBremen/yanic)
+[![CircleCI](https://circleci.com/gh/FreifunkBremen/yanic/tree/master.svg?style=shield)](https://circleci.com/gh/FreifunkBremen/yanic/tree/master)
 [![Coverage Status](https://coveralls.io/repos/github/FreifunkBremen/yanic/badge.svg?branch=master)](https://coveralls.io/github/FreifunkBremen/yanic?branch=master)
 [![codecov](https://codecov.io/gh/FreifunkBremen/yanic/branch/master/graph/badge.svg)](https://codecov.io/gh/FreifunkBremen/yanic)
 [![Go Report Card](https://goreportcard.com/badge/github.com/FreifunkBremen/yanic)](https://goreportcard.com/report/github.com/FreifunkBremen/yanic)
diff --git a/circle.yml b/circle.yml
new file mode 100644
index 0000000..8bed18b
--- /dev/null
+++ b/circle.yml
@@ -0,0 +1,41 @@
+version: 2
+jobs:
+  build:
+    docker:
+      - image: circleci/golang:latest
+    working_directory: /go/src/github.com/FreifunkBremen/yanic
+    steps:
+      - checkout
+      - run: go get -t -d -v ./...
+      - run: go install github.com/FreifunkBremen/yanic
+      - store_artifacts:
+          path: /go/bin/
+          destination: yanic
+  test:
+    docker:
+      - image: circleci/golang:latest
+    working_directory: /go/src/github.com/FreifunkBremen/yanic
+    steps:
+      - checkout
+      - run: go get -t -d -v ./...
+      - run: go get github.com/mattn/goveralls
+      - run: go get golang.org/x/tools/cmd/cover
+      - run: ./.test-coverage circle-ci
+      - store_test_results:
+          path: ./
+          destination: profile.cov
+  test_race:
+    docker:
+      - image: circleci/golang:latest
+    working_directory: /go/src/github.com/FreifunkBremen/yanic
+    steps:
+      - checkout
+      - run: go get -t -d -v ./...
+      - run: go test -race ./...
+workflows:
+  version: 2
+  build_and_tests:
+    jobs:
+      - build
+      - test
+      - test_race
diff --git a/output/all/internal_test.go b/output/all/internal_test.go
index ad067a3..ef87ba2 100644
--- a/output/all/internal_test.go
+++ b/output/all/internal_test.go
@@ -2,6 +2,7 @@ package all
 
 import (
 	"errors"
+	"sync"
 	"testing"
 
 	"github.com/FreifunkBremen/yanic/output"
@@ -11,11 +12,19 @@ import (
 
 type testOutput struct {
 	output.Output
-	CountSave int
+	countSave int
+	sync.Mutex
 }
 
 func (c *testOutput) Save(nodes *runtime.Nodes) {
-	c.CountSave++
+	c.Lock()
+	c.countSave++
+	c.Unlock()
+}
+func (c *testOutput) Get() int {
+	c.Lock()
+	defer c.Unlock()
+	return c.countSave
 }
 
 func TestStart(t *testing.T) {
@@ -69,9 +78,9 @@ func TestStart(t *testing.T) {
 	})
 	assert.NoError(err)
 
-	assert.Equal(0, globalOutput.CountSave)
+	assert.Equal(0, globalOutput.Get())
 	allOutput.Save(nodes)
-	assert.Equal(3, globalOutput.CountSave)
+	assert.Equal(3, globalOutput.Get())
 
 	_, err = Register(map[string]interface{}{
 		"e": []map[string]interface{}{
diff --git a/output/internal_test.go b/output/internal_test.go
index 9d9e9d0..72c7a11 100644
--- a/output/internal_test.go
+++ b/output/internal_test.go
@@ -1,6 +1,7 @@
 package output
 
 import (
+	"sync"
 	"testing"
 	"time"
 
@@ -10,11 +11,19 @@ import (
 
 type testConn struct {
 	Output
-	CountSave int
+	countSave int
+	sync.Mutex
 }
 
 func (c *testConn) Save(nodes *runtime.Nodes) {
-	c.CountSave++
+	c.Lock()
+	c.countSave++
+	c.Unlock()
+}
+func (c *testConn) Get() int {
+	c.Lock()
+	defer c.Unlock()
+	return c.countSave
 }
 
 func TestStart(t *testing.T) {
@@ -38,12 +47,12 @@ func TestStart(t *testing.T) {
 	Start(conn, nil, config)
 	assert.NotNil(quit)
 
-	assert.Equal(0, conn.CountSave)
+	assert.Equal(0, conn.Get())
 	time.Sleep(time.Millisecond * 12)
-	assert.Equal(1, conn.CountSave)
+	assert.Equal(1, conn.Get())
 
 	time.Sleep(time.Millisecond * 12)
 	Close()
-	assert.Equal(2, conn.CountSave)
+	assert.Equal(2, conn.Get())
 
 }