diff --git a/.travis.yml b/.travis.yml
index f369c43..449e3bc 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -12,8 +12,11 @@ script:
   - $(exit $(go fmt ./... | grep -v /vendor/ | wc -l))
 
   # Make sure go generate is in sync.
-  - go generate ./...
+  - go generate ./... && go install && go generate ./...
   - $(exit $(git status --porcelain | wc -l))
 
   # Run tests.
-  - go test -race ./...
+  - go test -race ./pie -coverprofile=coverage.txt -covermode=atomic
+
+after_success:
+  - bash <(curl -s https://codecov.io/bash)
diff --git a/README.md b/README.md
index 1dd82b4..8659688 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,7 @@
 # 🍕 `github.com/elliotchance/pie`
 [![GoDoc](https://godoc.org/github.com/elliotchance/pie?status.svg)](https://godoc.org/github.com/elliotchance/pie)
 [![Build Status](https://travis-ci.org/elliotchance/pie.svg?branch=master)](https://travis-ci.org/elliotchance/pie)
+[![codecov](https://codecov.io/gh/elliotchance/pie/branch/master/graph/badge.svg)](https://codecov.io/gh/elliotchance/pie)
 
 **Enjoy a slice!** `pie` is a code generator for dealing with slices that
 focuses on type safety, performance and immutability.
diff --git a/pie/myints_test.go b/pie/myints_test.go
new file mode 100644
index 0000000..49cc10a
--- /dev/null
+++ b/pie/myints_test.go
@@ -0,0 +1,18 @@
+package pie
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+// There tests are just to make sure that the select functions for myInts are
+// generated. The more extensive tests for these functions are in ints_test.go
+
+func TestMyInts_Average(t *testing.T) {
+	assert.Equal(t, 0.0, myInts(nil).Average())
+	assert.Equal(t, 4.333333333333333, myInts{1, 5, 7}.Average())
+}
+
+func TestMyInts_Sum(t *testing.T) {
+	assert.Equal(t, 13, myInts{1, 5, 7}.Sum())
+}