diff --git a/.travis.yml b/.travis.yml
index 65dcbc5..21166f5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,6 +1,11 @@
 language: go
 
 go:
-  - 1.8
-  - 1.7
-  - 1.6
\ No newline at end of file
+  - tip
+  - 1.15.x
+  - 1.14.x
+  - 1.13.x
+  - 1.12.x
+  
+env:
+  - GO111MODULE=on
diff --git a/chown_linux.go b/chown_linux.go
index 2758ec9..465f569 100644
--- a/chown_linux.go
+++ b/chown_linux.go
@@ -5,8 +5,8 @@ import (
 	"syscall"
 )
 
-// os_Chown is a var so we can mock it out during tests.
-var os_Chown = os.Chown
+// osChown is a var so we can mock it out during tests.
+var osChown = os.Chown
 
 func chown(name string, info os.FileInfo) error {
 	f, err := os.OpenFile(name, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, info.Mode())
@@ -15,5 +15,5 @@ func chown(name string, info os.FileInfo) error {
 	}
 	f.Close()
 	stat := info.Sys().(*syscall.Stat_t)
-	return os_Chown(name, int(stat.Uid), int(stat.Gid))
+	return osChown(name, int(stat.Uid), int(stat.Gid))
 }
diff --git a/example_test.go b/example_test.go
index df3dfb2..1da21e6 100644
--- a/example_test.go
+++ b/example_test.go
@@ -1,19 +1,17 @@
-package lumberjack_test
+package lumberjack
 
 import (
 	"log"
-
-	"gopkg.in/natefinch/lumberjack.v2"
 )
 
 // To use lumberjack with the standard library's log package, just pass it into
 // the SetOutput function when your application starts.
 func Example() {
-	log.SetOutput(&lumberjack.Logger{
+	log.SetOutput(&Logger{
 		Filename:   "/var/log/myapp/foo.log",
 		MaxSize:    500, // megabytes
 		MaxBackups: 3,
-		MaxAge:     28, // days
+		MaxAge:     28,   // days
 		Compress:   true, // disabled by default
 	})
 }
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..9061bae
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,8 @@
+module github.com/natefinch/lumberjack
+
+require (
+	github.com/BurntSushi/toml v0.3.1
+	gopkg.in/yaml.v2 v2.2.2
+)
+
+go 1.13
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..a2ea702
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,6 @@
+github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
+github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
diff --git a/linux_test.go b/linux_test.go
index 2bd1684..61dff04 100644
--- a/linux_test.go
+++ b/linux_test.go
@@ -48,11 +48,11 @@ func TestMaintainMode(t *testing.T) {
 
 func TestMaintainOwner(t *testing.T) {
 	fakeFS := newFakeFS()
-	os_Chown = fakeFS.Chown
-	os_Stat = fakeFS.Stat
+	osChown = fakeFS.Chown
+	osStat = fakeFS.Stat
 	defer func() {
-		os_Chown = os.Chown
-		os_Stat = os.Stat
+		osChown = os.Chown
+		osStat = os.Stat
 	}()
 	currentTime = fakeTime
 	dir := makeTempDir("TestMaintainOwner", t)
@@ -98,7 +98,7 @@ func TestCompressMaintainMode(t *testing.T) {
 	f.Close()
 
 	l := &Logger{
-		Compress: true,
+		Compress:   true,
 		Filename:   filename,
 		MaxBackups: 1,
 		MaxSize:    100, // megabytes
@@ -123,7 +123,7 @@ func TestCompressMaintainMode(t *testing.T) {
 	filename2 := backupFile(dir)
 	info, err := os.Stat(filename)
 	isNil(err, t)
-	info2, err := os.Stat(filename2+compressSuffix)
+	info2, err := os.Stat(filename2 + compressSuffix)
 	isNil(err, t)
 	equals(mode, info.Mode(), t)
 	equals(mode, info2.Mode(), t)
@@ -131,11 +131,11 @@ func TestCompressMaintainMode(t *testing.T) {
 
 func TestCompressMaintainOwner(t *testing.T) {
 	fakeFS := newFakeFS()
-	os_Chown = fakeFS.Chown
-	os_Stat = fakeFS.Stat
+	osChown = fakeFS.Chown
+	osStat = fakeFS.Stat
 	defer func() {
-		os_Chown = os.Chown
-		os_Stat = os.Stat
+		osChown = os.Chown
+		osStat = os.Stat
 	}()
 	currentTime = fakeTime
 	dir := makeTempDir("TestCompressMaintainOwner", t)
diff --git a/lumberjack.go b/lumberjack.go
index a47b7f0..3447cdc 100644
--- a/lumberjack.go
+++ b/lumberjack.go
@@ -120,7 +120,7 @@ var (
 	currentTime = time.Now
 
 	// os_Stat exists so it can be mocked out by tests.
-	os_Stat = os.Stat
+	osStat = os.Stat
 
 	// megabyte is the conversion factor between MaxSize and bytes.  It is a
 	// variable so tests can mock it out and not need to write megabytes of data
@@ -213,7 +213,7 @@ func (l *Logger) openNew() error {
 
 	name := l.filename()
 	mode := os.FileMode(0600)
-	info, err := os_Stat(name)
+	info, err := osStat(name)
 	if err == nil {
 		// Copy the mode off the old logfile.
 		mode = info.Mode()
@@ -265,7 +265,7 @@ func (l *Logger) openExistingOrNew(writeLen int) error {
 	l.mill()
 
 	filename := l.filename()
-	info, err := os_Stat(filename)
+	info, err := osStat(filename)
 	if os.IsNotExist(err) {
 		return l.openNew()
 	}
@@ -376,7 +376,7 @@ func (l *Logger) millRunOnce() error {
 // millRun runs in a goroutine to manage post-rotation compression and removal
 // of old log files.
 func (l *Logger) millRun() {
-	for _ = range l.millCh {
+	for range l.millCh {
 		// what am I going to do, log this?
 		_ = l.millRunOnce()
 	}
@@ -472,7 +472,7 @@ func compressLogFile(src, dst string) (err error) {
 	}
 	defer f.Close()
 
-	fi, err := os_Stat(src)
+	fi, err := osStat(src)
 	if err != nil {
 		return fmt.Errorf("failed to stat log file: %v", err)
 	}
diff --git a/rotate_test.go b/rotate_test.go
index 4bd4325..453bf14 100644
--- a/rotate_test.go
+++ b/rotate_test.go
@@ -1,19 +1,17 @@
 // +build linux
 
-package lumberjack_test
+package lumberjack
 
 import (
 	"log"
 	"os"
 	"os/signal"
 	"syscall"
-
-	"gopkg.in/natefinch/lumberjack.v2"
 )
 
 // Example of how to rotate in response to SIGHUP.
 func ExampleLogger_Rotate() {
-	l := &lumberjack.Logger{}
+	l := &Logger{}
 	log.SetOutput(l)
 	c := make(chan os.Signal, 1)
 	signal.Notify(c, syscall.SIGHUP)