diff --git a/.github/ISSUE_TEMPLATE.md b/.github/ISSUE_TEMPLATE.md
index de067ce0..9d49aa41 100644
--- a/.github/ISSUE_TEMPLATE.md
+++ b/.github/ISSUE_TEMPLATE.md
@@ -3,8 +3,8 @@
   - Please provide source code and commit sha if you found a bug.
   - Review existing issues and provide feedback or react to them.
 
+- go version:
 - gin version (or commit ref):
-- git version:
 - operating system:
 
 ## Description
diff --git a/.travis.yml b/.travis.yml
index a93458f9..398c1409 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,6 +7,11 @@ go:
   - 1.9.x
   - 1.10.x
   - 1.11.x
+  - master
+
+matrix:
+  allow_failures:
+    - go: master
 
 git:
   depth: 10
diff --git a/README.md b/README.md
index d852f97d..6fd2dd34 100644
--- a/README.md
+++ b/README.md
@@ -59,6 +59,7 @@ Gin is a web framework written in Go (Golang). It features a martini-like API wi
     - [Bind form-data request with custom struct](#bind-form-data-request-with-custom-struct)
     - [Try to bind body into different structs](#try-to-bind-body-into-different-structs)
     - [http2 server push](#http2-server-push)
+    - [Define format for the log of routes](#define-format-for-the-log-of-routes)
 - [Testing](#testing)
 - [Users](#users)
 
@@ -658,6 +659,7 @@ import (
 	"gopkg.in/go-playground/validator.v8"
 )
 
+// Booking contains binded and validated data.
 type Booking struct {
 	CheckIn  time.Time `form:"check_in" binding:"required,bookabledate" time_format:"2006-01-02"`
 	CheckOut time.Time `form:"check_out" binding:"required,gtfield=CheckIn" time_format:"2006-01-02"`
@@ -1836,6 +1838,49 @@ func main() {
 }
 ```
 
+### Define format for the log of routes
+
+The default log of routes is:
+```
+[GIN-debug] POST   /foo                      --> main.main.func1 (3 handlers)
+[GIN-debug] GET    /bar                      --> main.main.func2 (3 handlers)
+[GIN-debug] GET    /status                   --> main.main.func3 (3 handlers)
+```
+
+If you want to log this information in given format (e.g. JSON, key values or something else), then you can define this format with `gin.DebugPrintRouteFunc`.
+In the example below, we log all routes with standard log package but you can use another log tools that suits of your needs.
+```go
+import (
+	"log"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+)
+
+func main() {
+	r := gin.Default()
+	gin.DebugPrintRouteFunc = func(httpMethod, absolutePath, handlerName string, nuHandlers int) {
+		log.Printf("endpoint %v %v %v %v\n", httpMethod, absolutePath, handlerName, nuHandlers)
+	}
+
+	r.POST("/foo", func(c *gin.Context) {
+		c.JSON(http.StatusOK, "foo")
+	})
+
+	r.GET("/bar", func(c *gin.Context) {
+		c.JSON(http.StatusOK, "bar")
+	})
+
+	r.GET("/status", func(c *gin.Context) {
+		c.JSON(http.StatusOK, "ok")
+	})
+
+	// Listen and Server in http://0.0.0.0:8080
+	r.Run()
+}
+```
+
+
 ## Testing
 
 The `net/http/httptest` package is preferable way for HTTP testing.
@@ -1886,5 +1931,6 @@ func TestPingRoute(t *testing.T) {
 
 Awesome project lists using [Gin](https://github.com/gin-gonic/gin) web framework.
 
-* [drone](https://github.com/drone/drone): Drone is a Continuous Delivery platform built on Docker, written in Go
+* [drone](https://github.com/drone/drone): Drone is a Continuous Delivery platform built on Docker, written in Go.
 * [gorush](https://github.com/appleboy/gorush): A push notification server written in Go.
+* [fnproject](https://github.com/fnproject/fn): The container native, cloud agnostic serverless platform.
diff --git a/context.go b/context.go
index 063c72f0..809902a3 100644
--- a/context.go
+++ b/context.go
@@ -711,6 +711,7 @@ func (c *Context) Cookie(name string) (string, error) {
 	return val, nil
 }
 
+// Render writes the response headers and calls render.Render to render data.
 func (c *Context) Render(code int, r render.Render) {
 	c.Status(code)
 
@@ -833,6 +834,7 @@ func (c *Context) SSEvent(name string, message interface{}) {
 	})
 }
 
+// Stream sends a streaming response.
 func (c *Context) Stream(step func(w io.Writer) bool) {
 	w := c.Writer
 	clientGone := w.CloseNotify()
@@ -854,6 +856,7 @@ func (c *Context) Stream(step func(w io.Writer) bool) {
 /******** CONTENT NEGOTIATION *******/
 /************************************/
 
+// Negotiate contains all negotiations data.
 type Negotiate struct {
 	Offered  []string
 	HTMLName string
@@ -863,6 +866,7 @@ type Negotiate struct {
 	Data     interface{}
 }
 
+// Negotiate calls different Render according acceptable Accept format.
 func (c *Context) Negotiate(code int, config Negotiate) {
 	switch c.NegotiateFormat(config.Offered...) {
 	case binding.MIMEJSON:
@@ -882,6 +886,7 @@ func (c *Context) Negotiate(code int, config Negotiate) {
 	}
 }
 
+// NegotiateFormat returns an acceptable Accept format.
 func (c *Context) NegotiateFormat(offered ...string) string {
 	assert1(len(offered) > 0, "you must provide at least one offer")
 
@@ -901,6 +906,7 @@ func (c *Context) NegotiateFormat(offered ...string) string {
 	return ""
 }
 
+// SetAccepted sets Accept header data.
 func (c *Context) SetAccepted(formats ...string) {
 	c.Accepted = formats
 }
diff --git a/context_test.go b/context_test.go
index 782f7bed..5a5bb6e1 100644
--- a/context_test.go
+++ b/context_test.go
@@ -784,14 +784,14 @@ func TestContextRenderHTML2(t *testing.T) {
 	router.addRoute("GET", "/", HandlersChain{func(_ *Context) {}})
 	assert.Len(t, router.trees, 1)
 
-	var b bytes.Buffer
-	setup(&b)
-	defer teardown()
-
 	templ := template.Must(template.New("t").Parse(`Hello {{.name}}`))
-	router.SetHTMLTemplate(templ)
+	re := captureOutput(func() {
+		SetMode(DebugMode)
+		router.SetHTMLTemplate(templ)
+		SetMode(TestMode)
+	})
 
-	assert.Equal(t, "[GIN-debug] [WARNING] Since SetHTMLTemplate() is NOT thread-safe. It should only be called\nat initialization. ie. before any route is registered or the router is listening in a socket:\n\n\trouter := gin.Default()\n\trouter.SetHTMLTemplate(template) // << good place\n\n", b.String())
+	assert.Equal(t, "[GIN-debug] [WARNING] Since SetHTMLTemplate() is NOT thread-safe. It should only be called\nat initialization. ie. before any route is registered or the router is listening in a socket:\n\n\trouter := gin.Default()\n\trouter.SetHTMLTemplate(template) // << good place\n\n", re)
 
 	c.HTML(http.StatusCreated, "t", H{"name": "alexandernyquist"})
 
@@ -978,7 +978,7 @@ func TestContextRenderProtoBuf(t *testing.T) {
 	assert.NoError(t, err)
 
 	assert.Equal(t, http.StatusCreated, w.Code)
-	assert.Equal(t, string(protoData[:]), w.Body.String())
+	assert.Equal(t, string(protoData), w.Body.String())
 	assert.Equal(t, "application/x-protobuf", w.HeaderMap.Get("Content-Type"))
 }
 
diff --git a/debug.go b/debug.go
index f11156b3..ce908dc7 100644
--- a/debug.go
+++ b/debug.go
@@ -6,25 +6,28 @@ package gin
 
 import (
 	"bytes"
+	"fmt"
 	"html/template"
-	"log"
 )
 
-func init() {
-	log.SetFlags(0)
-}
-
 // IsDebugging returns true if the framework is running in debug mode.
 // Use SetMode(gin.ReleaseMode) to disable debug mode.
 func IsDebugging() bool {
 	return ginMode == debugCode
 }
 
+// DebugPrintRouteFunc indicates debug log output format.
+var DebugPrintRouteFunc func(httpMethod, absolutePath, handlerName string, nuHandlers int)
+
 func debugPrintRoute(httpMethod, absolutePath string, handlers HandlersChain) {
 	if IsDebugging() {
 		nuHandlers := len(handlers)
 		handlerName := nameOfFunction(handlers.Last())
-		debugPrint("%-6s %-25s --> %s (%d handlers)\n", httpMethod, absolutePath, handlerName, nuHandlers)
+		if DebugPrintRouteFunc == nil {
+			debugPrint("%-6s %-25s --> %s (%d handlers)\n", httpMethod, absolutePath, handlerName, nuHandlers)
+		} else {
+			DebugPrintRouteFunc(httpMethod, absolutePath, handlerName, nuHandlers)
+		}
 	}
 }
 
@@ -42,7 +45,7 @@ func debugPrintLoadTemplate(tmpl *template.Template) {
 
 func debugPrint(format string, values ...interface{}) {
 	if IsDebugging() {
-		log.Printf("[GIN-debug] "+format, values...)
+		fmt.Printf("[GIN-debug] "+format, values...)
 	}
 }
 
diff --git a/debug_test.go b/debug_test.go
index ed5a6a54..0b9d7910 100644
--- a/debug_test.go
+++ b/debug_test.go
@@ -11,6 +11,7 @@ import (
 	"io"
 	"log"
 	"os"
+	"sync"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -30,86 +31,101 @@ func TestIsDebugging(t *testing.T) {
 }
 
 func TestDebugPrint(t *testing.T) {
-	var w bytes.Buffer
-	setup(&w)
-	defer teardown()
-
-	SetMode(ReleaseMode)
-	debugPrint("DEBUG this!")
-	SetMode(TestMode)
-	debugPrint("DEBUG this!")
-	assert.Empty(t, w.String())
-
-	SetMode(DebugMode)
-	debugPrint("these are %d %s\n", 2, "error messages")
-	assert.Equal(t, "[GIN-debug] these are 2 error messages\n", w.String())
+	re := captureOutput(func() {
+		SetMode(DebugMode)
+		SetMode(ReleaseMode)
+		debugPrint("DEBUG this!")
+		SetMode(TestMode)
+		debugPrint("DEBUG this!")
+		SetMode(DebugMode)
+		debugPrint("these are %d %s\n", 2, "error messages")
+		SetMode(TestMode)
+	})
+	assert.Equal(t, "[GIN-debug] these are 2 error messages\n", re)
 }
 
 func TestDebugPrintError(t *testing.T) {
-	var w bytes.Buffer
-	setup(&w)
-	defer teardown()
-
-	SetMode(DebugMode)
-	debugPrintError(nil)
-	assert.Empty(t, w.String())
-
-	debugPrintError(errors.New("this is an error"))
-	assert.Equal(t, "[GIN-debug] [ERROR] this is an error\n", w.String())
+	re := captureOutput(func() {
+		SetMode(DebugMode)
+		debugPrintError(nil)
+		debugPrintError(errors.New("this is an error"))
+		SetMode(TestMode)
+	})
+	assert.Equal(t, "[GIN-debug] [ERROR] this is an error\n", re)
 }
 
 func TestDebugPrintRoutes(t *testing.T) {
-	var w bytes.Buffer
-	setup(&w)
-	defer teardown()
-
-	debugPrintRoute("GET", "/path/to/route/:param", HandlersChain{func(c *Context) {}, handlerNameTest})
-	assert.Regexp(t, `^\[GIN-debug\] GET    /path/to/route/:param     --> (.*/vendor/)?github.com/gin-gonic/gin.handlerNameTest \(2 handlers\)\n$`, w.String())
+	re := captureOutput(func() {
+		SetMode(DebugMode)
+		debugPrintRoute("GET", "/path/to/route/:param", HandlersChain{func(c *Context) {}, handlerNameTest})
+		SetMode(TestMode)
+	})
+	assert.Regexp(t, `^\[GIN-debug\] GET    /path/to/route/:param     --> (.*/vendor/)?github.com/gin-gonic/gin.handlerNameTest \(2 handlers\)\n$`, re)
 }
 
 func TestDebugPrintLoadTemplate(t *testing.T) {
-	var w bytes.Buffer
-	setup(&w)
-	defer teardown()
-
-	templ := template.Must(template.New("").Delims("{[{", "}]}").ParseGlob("./testdata/template/hello.tmpl"))
-	debugPrintLoadTemplate(templ)
-	assert.Regexp(t, `^\[GIN-debug\] Loaded HTML Templates \(2\): \n(\t- \n|\t- hello\.tmpl\n){2}\n`, w.String())
+	re := captureOutput(func() {
+		SetMode(DebugMode)
+		templ := template.Must(template.New("").Delims("{[{", "}]}").ParseGlob("./testdata/template/hello.tmpl"))
+		debugPrintLoadTemplate(templ)
+		SetMode(TestMode)
+	})
+	assert.Regexp(t, `^\[GIN-debug\] Loaded HTML Templates \(2\): \n(\t- \n|\t- hello\.tmpl\n){2}\n`, re)
 }
 
 func TestDebugPrintWARNINGSetHTMLTemplate(t *testing.T) {
-	var w bytes.Buffer
-	setup(&w)
-	defer teardown()
-
-	debugPrintWARNINGSetHTMLTemplate()
-	assert.Equal(t, "[GIN-debug] [WARNING] Since SetHTMLTemplate() is NOT thread-safe. It should only be called\nat initialization. ie. before any route is registered or the router is listening in a socket:\n\n\trouter := gin.Default()\n\trouter.SetHTMLTemplate(template) // << good place\n\n", w.String())
+	re := captureOutput(func() {
+		SetMode(DebugMode)
+		debugPrintWARNINGSetHTMLTemplate()
+		SetMode(TestMode)
+	})
+	assert.Equal(t, "[GIN-debug] [WARNING] Since SetHTMLTemplate() is NOT thread-safe. It should only be called\nat initialization. ie. before any route is registered or the router is listening in a socket:\n\n\trouter := gin.Default()\n\trouter.SetHTMLTemplate(template) // << good place\n\n", re)
 }
 
 func TestDebugPrintWARNINGDefault(t *testing.T) {
-	var w bytes.Buffer
-	setup(&w)
-	defer teardown()
-
-	debugPrintWARNINGDefault()
-	assert.Equal(t, "[GIN-debug] [WARNING] Now Gin requires Go 1.6 or later and Go 1.7 will be required soon.\n\n[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.\n\n", w.String())
+	re := captureOutput(func() {
+		SetMode(DebugMode)
+		debugPrintWARNINGDefault()
+		SetMode(TestMode)
+	})
+	assert.Equal(t, "[GIN-debug] [WARNING] Now Gin requires Go 1.6 or later and Go 1.7 will be required soon.\n\n[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.\n\n", re)
 }
 
 func TestDebugPrintWARNINGNew(t *testing.T) {
-	var w bytes.Buffer
-	setup(&w)
-	defer teardown()
-
-	debugPrintWARNINGNew()
-	assert.Equal(t, "[GIN-debug] [WARNING] Running in \"debug\" mode. Switch to \"release\" mode in production.\n - using env:\texport GIN_MODE=release\n - using code:\tgin.SetMode(gin.ReleaseMode)\n\n", w.String())
+	re := captureOutput(func() {
+		SetMode(DebugMode)
+		debugPrintWARNINGNew()
+		SetMode(TestMode)
+	})
+	assert.Equal(t, "[GIN-debug] [WARNING] Running in \"debug\" mode. Switch to \"release\" mode in production.\n - using env:\texport GIN_MODE=release\n - using code:\tgin.SetMode(gin.ReleaseMode)\n\n", re)
 }
 
-func setup(w io.Writer) {
-	SetMode(DebugMode)
-	log.SetOutput(w)
-}
-
-func teardown() {
-	SetMode(TestMode)
-	log.SetOutput(os.Stdout)
+func captureOutput(f func()) string {
+	reader, writer, err := os.Pipe()
+	if err != nil {
+		panic(err)
+	}
+	stdout := os.Stdout
+	stderr := os.Stderr
+	defer func() {
+		os.Stdout = stdout
+		os.Stderr = stderr
+		log.SetOutput(os.Stderr)
+	}()
+	os.Stdout = writer
+	os.Stderr = writer
+	log.SetOutput(writer)
+	out := make(chan string)
+	wg := new(sync.WaitGroup)
+	wg.Add(1)
+	go func() {
+		var buf bytes.Buffer
+		wg.Done()
+		io.Copy(&buf, reader)
+		out <- buf.String()
+	}()
+	wg.Wait()
+	f()
+	writer.Close()
+	return <-out
 }
diff --git a/errors.go b/errors.go
index 6f90377e..477b9d58 100644
--- a/errors.go
+++ b/errors.go
@@ -12,18 +12,24 @@ import (
 	"github.com/gin-gonic/gin/internal/json"
 )
 
+// ErrorType is an unsigned 64-bit error code as defined in the gin spec.
 type ErrorType uint64
 
 const (
-	ErrorTypeBind    ErrorType = 1 << 63 // used when c.Bind() fails
-	ErrorTypeRender  ErrorType = 1 << 62 // used when c.Render() fails
+	// ErrorTypeBind is used when Context.Bind() fails.
+	ErrorTypeBind ErrorType = 1 << 63
+	// ErrorTypeRender is used when Context.Render() fails.
+	ErrorTypeRender ErrorType = 1 << 62
+	// ErrorTypePrivate indicates a private error.
 	ErrorTypePrivate ErrorType = 1 << 0
-	ErrorTypePublic  ErrorType = 1 << 1
-
+	// ErrorTypePublic indicates a public error.
+	ErrorTypePublic ErrorType = 1 << 1
+	// ErrorTypeAny indicates other any error.
 	ErrorTypeAny ErrorType = 1<<64 - 1
 	ErrorTypeNu            = 2
 )
 
+// Error represents a error's specification.
 type Error struct {
 	Err  error
 	Type ErrorType
@@ -34,11 +40,13 @@ type errorMsgs []*Error
 
 var _ error = &Error{}
 
+// SetType sets the error's type.
 func (msg *Error) SetType(flags ErrorType) *Error {
 	msg.Type = flags
 	return msg
 }
 
+// SetMeta sets the error's meta data.
 func (msg *Error) SetMeta(data interface{}) *Error {
 	msg.Meta = data
 	return msg
@@ -70,11 +78,12 @@ func (msg *Error) MarshalJSON() ([]byte, error) {
 	return json.Marshal(msg.JSON())
 }
 
-// Error implements the error interface
+// Error implements the error interface.
 func (msg Error) Error() string {
 	return msg.Err.Error()
 }
 
+// IsType judges one error.
 func (msg *Error) IsType(flags ErrorType) bool {
 	return (msg.Type & flags) > 0
 }
@@ -138,6 +147,7 @@ func (a errorMsgs) JSON() interface{} {
 	}
 }
 
+// MarshalJSON implements the json.Marshaller interface.
 func (a errorMsgs) MarshalJSON() ([]byte, error) {
 	return json.Marshal(a.JSON())
 }
diff --git a/examples/basic/main.go b/examples/basic/main.go
index 48fa7bba..1c9e0ac4 100644
--- a/examples/basic/main.go
+++ b/examples/basic/main.go
@@ -6,7 +6,7 @@ import (
 	"github.com/gin-gonic/gin"
 )
 
-var DB = make(map[string]string)
+var db = make(map[string]string)
 
 func setupRouter() *gin.Engine {
 	// Disable Console Color
@@ -21,7 +21,7 @@ func setupRouter() *gin.Engine {
 	// Get user value
 	r.GET("/user/:name", func(c *gin.Context) {
 		user := c.Params.ByName("name")
-		value, ok := DB[user]
+		value, ok := db[user]
 		if ok {
 			c.JSON(http.StatusOK, gin.H{"user": user, "value": value})
 		} else {
@@ -50,7 +50,7 @@ func setupRouter() *gin.Engine {
 		}
 
 		if c.Bind(&json) == nil {
-			DB[user] = json.Value
+			db[user] = json.Value
 			c.JSON(http.StatusOK, gin.H{"status": "ok"})
 		}
 	})
diff --git a/examples/custom-validation/server.go b/examples/custom-validation/server.go
index dea0c302..9238200b 100644
--- a/examples/custom-validation/server.go
+++ b/examples/custom-validation/server.go
@@ -10,6 +10,7 @@ import (
 	"gopkg.in/go-playground/validator.v8"
 )
 
+// Booking contains binded and validated data.
 type Booking struct {
 	CheckIn  time.Time `form:"check_in" binding:"required,bookabledate" time_format:"2006-01-02"`
 	CheckOut time.Time `form:"check_out" binding:"required,gtfield=CheckIn" time_format:"2006-01-02"`
diff --git a/examples/realtime-advanced/main.go b/examples/realtime-advanced/main.go
index 1f3c8585..f3ead476 100644
--- a/examples/realtime-advanced/main.go
+++ b/examples/realtime-advanced/main.go
@@ -13,16 +13,19 @@ func main() {
 	StartGin()
 }
 
+// ConfigRuntime sets the number of operating system threads.
 func ConfigRuntime() {
 	nuCPU := runtime.NumCPU()
 	runtime.GOMAXPROCS(nuCPU)
 	fmt.Printf("Running with %d CPUs\n", nuCPU)
 }
 
+// StartWorkers start starsWorker by goroutine.
 func StartWorkers() {
 	go statsWorker()
 }
 
+// StartGin starts gin web server with setting router.
 func StartGin() {
 	gin.SetMode(gin.ReleaseMode)
 
diff --git a/examples/realtime-advanced/stats.go b/examples/realtime-advanced/stats.go
index 4afedcb5..a6488035 100644
--- a/examples/realtime-advanced/stats.go
+++ b/examples/realtime-advanced/stats.go
@@ -50,6 +50,7 @@ func connectedUsers() uint64 {
 	return uint64(connected)
 }
 
+// Stats returns savedStats data.
 func Stats() map[string]uint64 {
 	mutexStats.RLock()
 	defer mutexStats.RUnlock()
diff --git a/gin.go b/gin.go
index aa62e014..11f6d94a 100644
--- a/gin.go
+++ b/gin.go
@@ -14,11 +14,7 @@ import (
 	"github.com/gin-gonic/gin/render"
 )
 
-const (
-	// Version is Framework's version.
-	Version                = "v1.3.0"
-	defaultMultipartMemory = 32 << 20 // 32 MB
-)
+const defaultMultipartMemory = 32 << 20 // 32 MB
 
 var (
 	default404Body   = []byte("404 page not found")
@@ -26,7 +22,10 @@ var (
 	defaultAppEngine bool
 )
 
+// HandlerFunc defines the handler used by gin middleware as return value.
 type HandlerFunc func(*Context)
+
+// HandlersChain defines a HandlerFunc array.
 type HandlersChain []HandlerFunc
 
 // Last returns the last handler in the chain. ie. the last handler is the main own.
@@ -37,12 +36,14 @@ func (c HandlersChain) Last() HandlerFunc {
 	return nil
 }
 
+// RouteInfo represents a request route's specification which contains method and path and its handler.
 type RouteInfo struct {
 	Method  string
 	Path    string
 	Handler string
 }
 
+// RoutesInfo defines a RouteInfo array.
 type RoutesInfo []RouteInfo
 
 // Engine is the framework's instance, it contains the muxer, middleware and configuration settings.
@@ -155,6 +156,7 @@ func (engine *Engine) allocateContext() *Context {
 	return &Context{engine: engine}
 }
 
+// Delims sets template left and right delims and returns a Engine instance.
 func (engine *Engine) Delims(left, right string) *Engine {
 	engine.delims = render.Delims{Left: left, Right: right}
 	return engine
diff --git a/ginS/gins.go b/ginS/gins.go
index a7686f23..04cf131c 100644
--- a/ginS/gins.go
+++ b/ginS/gins.go
@@ -22,14 +22,17 @@ func engine() *gin.Engine {
 	return internalEngine
 }
 
+// LoadHTMLGlob is a wrapper for Engine.LoadHTMLGlob.
 func LoadHTMLGlob(pattern string) {
 	engine().LoadHTMLGlob(pattern)
 }
 
+// LoadHTMLFiles is a wrapper for Engine.LoadHTMLFiles.
 func LoadHTMLFiles(files ...string) {
 	engine().LoadHTMLFiles(files...)
 }
 
+// SetHTMLTemplate is a wrapper for Engine.SetHTMLTemplate.
 func SetHTMLTemplate(templ *template.Template) {
 	engine().SetHTMLTemplate(templ)
 }
@@ -39,7 +42,7 @@ func NoRoute(handlers ...gin.HandlerFunc) {
 	engine().NoRoute(handlers...)
 }
 
-// NoMethod sets the handlers called when... TODO
+// NoMethod is a wrapper for Engine.NoMethod.
 func NoMethod(handlers ...gin.HandlerFunc) {
 	engine().NoMethod(handlers...)
 }
@@ -50,6 +53,7 @@ func Group(relativePath string, handlers ...gin.HandlerFunc) *gin.RouterGroup {
 	return engine().Group(relativePath, handlers...)
 }
 
+// Handle is a wrapper for Engine.Handle.
 func Handle(httpMethod, relativePath string, handlers ...gin.HandlerFunc) gin.IRoutes {
 	return engine().Handle(httpMethod, relativePath, handlers...)
 }
@@ -89,10 +93,12 @@ func HEAD(relativePath string, handlers ...gin.HandlerFunc) gin.IRoutes {
 	return engine().HEAD(relativePath, handlers...)
 }
 
+// Any is a wrapper for Engine.Any.
 func Any(relativePath string, handlers ...gin.HandlerFunc) gin.IRoutes {
 	return engine().Any(relativePath, handlers...)
 }
 
+// StaticFile is a wrapper for Engine.StaticFile.
 func StaticFile(relativePath, filepath string) gin.IRoutes {
 	return engine().StaticFile(relativePath, filepath)
 }
@@ -107,6 +113,7 @@ func Static(relativePath, root string) gin.IRoutes {
 	return engine().Static(relativePath, root)
 }
 
+// StaticFS is a wrapper for Engine.StaticFS.
 func StaticFS(relativePath string, fs http.FileSystem) gin.IRoutes {
 	return engine().StaticFS(relativePath, fs)
 }
diff --git a/gin_test.go b/gin_test.go
index b3cab715..95b9cc16 100644
--- a/gin_test.go
+++ b/gin_test.go
@@ -88,7 +88,7 @@ func TestLoadHTMLGlob(t *testing.T) {
 	}
 
 	resp, _ := ioutil.ReadAll(res.Body)
-	assert.Equal(t, "<h1>Hello world</h1>", string(resp[:]))
+	assert.Equal(t, "<h1>Hello world</h1>", string(resp))
 
 	td()
 }
@@ -101,7 +101,7 @@ func TestLoadHTMLGlob2(t *testing.T) {
 	}
 
 	resp, _ := ioutil.ReadAll(res.Body)
-	assert.Equal(t, "<h1>Hello world</h1>", string(resp[:]))
+	assert.Equal(t, "<h1>Hello world</h1>", string(resp))
 
 	td()
 }
@@ -114,7 +114,7 @@ func TestLoadHTMLGlob3(t *testing.T) {
 	}
 
 	resp, _ := ioutil.ReadAll(res.Body)
-	assert.Equal(t, "<h1>Hello world</h1>", string(resp[:]))
+	assert.Equal(t, "<h1>Hello world</h1>", string(resp))
 
 	td()
 }
@@ -134,7 +134,7 @@ func TestLoadHTMLGlobUsingTLS(t *testing.T) {
 	}
 
 	resp, _ := ioutil.ReadAll(res.Body)
-	assert.Equal(t, "<h1>Hello world</h1>", string(resp[:]))
+	assert.Equal(t, "<h1>Hello world</h1>", string(resp))
 
 	td()
 }
@@ -148,7 +148,7 @@ func TestLoadHTMLGlobFromFuncMap(t *testing.T) {
 	}
 
 	resp, _ := ioutil.ReadAll(res.Body)
-	assert.Equal(t, "Date: 2017/07/01\n", string(resp[:]))
+	assert.Equal(t, "Date: 2017/07/01\n", string(resp))
 
 	td()
 }
@@ -187,7 +187,7 @@ func TestLoadHTMLFiles(t *testing.T) {
 	}
 
 	resp, _ := ioutil.ReadAll(res.Body)
-	assert.Equal(t, "<h1>Hello world</h1>", string(resp[:]))
+	assert.Equal(t, "<h1>Hello world</h1>", string(resp))
 	td()
 }
 
@@ -199,7 +199,7 @@ func TestLoadHTMLFiles2(t *testing.T) {
 	}
 
 	resp, _ := ioutil.ReadAll(res.Body)
-	assert.Equal(t, "<h1>Hello world</h1>", string(resp[:]))
+	assert.Equal(t, "<h1>Hello world</h1>", string(resp))
 	td()
 }
 
@@ -211,7 +211,7 @@ func TestLoadHTMLFiles3(t *testing.T) {
 	}
 
 	resp, _ := ioutil.ReadAll(res.Body)
-	assert.Equal(t, "<h1>Hello world</h1>", string(resp[:]))
+	assert.Equal(t, "<h1>Hello world</h1>", string(resp))
 	td()
 }
 
@@ -230,7 +230,7 @@ func TestLoadHTMLFilesUsingTLS(t *testing.T) {
 	}
 
 	resp, _ := ioutil.ReadAll(res.Body)
-	assert.Equal(t, "<h1>Hello world</h1>", string(resp[:]))
+	assert.Equal(t, "<h1>Hello world</h1>", string(resp))
 	td()
 }
 
@@ -243,7 +243,7 @@ func TestLoadHTMLFilesFuncMap(t *testing.T) {
 	}
 
 	resp, _ := ioutil.ReadAll(res.Body)
-	assert.Equal(t, "Date: 2017/07/01\n", string(resp[:]))
+	assert.Equal(t, "Date: 2017/07/01\n", string(resp))
 
 	td()
 }
diff --git a/go.mod b/go.mod
new file mode 100644
index 00000000..bd4ad975
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,27 @@
+module github.com/gin-gonic/gin
+
+require (
+	github.com/davecgh/go-spew v0.0.0-20180221232628-8991bc29aa16 // indirect
+	github.com/dustin/go-broadcast v0.0.0-20171205050544-f664265f5a66
+	github.com/gin-contrib/sse v0.0.0-20170109093832-22d885f9ecc7
+	github.com/gin-gonic/autotls v0.0.0-20180426091246-be87bd5ef97b
+	github.com/golang/protobuf v1.2.0
+	github.com/jessevdk/go-assets v0.0.0-20160921144138-4f4301a06e15
+	github.com/json-iterator/go v0.0.0-20180806060727-1624edc4454b
+	github.com/manucorporat/stats v0.0.0-20180402194714-3ba42d56d227
+	github.com/mattn/go-isatty v0.0.3
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/stretchr/testify v1.2.2
+	github.com/thinkerou/favicon v0.0.0-20170710140520-94a442a49da6
+	github.com/ugorji/go v1.1.1
+	golang.org/x/crypto v0.0.0-20180910181607-0e37d006457b
+	golang.org/x/net v0.0.0-20180826012351-8a410e7b638d
+	golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f
+	golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e // indirect
+	google.golang.org/grpc v1.15.0
+	gopkg.in/go-playground/assert.v1 v1.2.1 // indirect
+	gopkg.in/go-playground/validator.v8 v8.18.2
+	gopkg.in/yaml.v2 v2.2.1
+)
diff --git a/go.sum b/go.sum
new file mode 100644
index 00000000..3382beed
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,65 @@
+cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
+github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
+github.com/davecgh/go-spew v0.0.0-20180221232628-8991bc29aa16 h1:HqkufMBR7waVfFFRABWqHa1WgTvjtVDJTLJe3CR576A=
+github.com/davecgh/go-spew v0.0.0-20180221232628-8991bc29aa16/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/dustin/go-broadcast v0.0.0-20171205050544-f664265f5a66 h1:QnnoVdChKs+GeTvN4rPYTW6b5U6M3HMEvQ/+x4IGtfY=
+github.com/dustin/go-broadcast v0.0.0-20171205050544-f664265f5a66/go.mod h1:kTEh6M2J/mh7nsskr28alwLCXm/DSG5OSA/o31yy2XU=
+github.com/gin-contrib/sse v0.0.0-20170109093832-22d885f9ecc7 h1:AzN37oI0cOS+cougNAV9szl6CVoj2RYwzS3DpUQNtlY=
+github.com/gin-contrib/sse v0.0.0-20170109093832-22d885f9ecc7/go.mod h1:VJ0WA2NBN22VlZ2dKZQPAPnyWw5XTlK1KymzLKsr59s=
+github.com/gin-gonic/autotls v0.0.0-20180426091246-be87bd5ef97b h1:dm/NYytoj7p8Jc6zMvyRz3PCQrTTCXnVRvEzyBcM890=
+github.com/gin-gonic/autotls v0.0.0-20180426091246-be87bd5ef97b/go.mod h1:vwfeXwKgEIWq63oVfwaBjoByS4dZzYbHHROHjV4IjNY=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b h1:VKtxabqXZkF25pY9ekfRL6a582T4P37/31XEstQ5p58=
+github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
+github.com/golang/lint v0.0.0-20180702182130-06c8688daad7/go.mod h1:tluoj9z5200jBnyusfRPU2LqT6J+DAorxEvtC7LHB+E=
+github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
+github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
+github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/jessevdk/go-assets v0.0.0-20160921144138-4f4301a06e15 h1:cW/amwGEJK5MSKntPXRjX4dxs/nGxGT8gXKIsKFmHGc=
+github.com/jessevdk/go-assets v0.0.0-20160921144138-4f4301a06e15/go.mod h1:Fdm/oWRW+CH8PRbLntksCNtmcCBximKPkVQYvmMl80k=
+github.com/json-iterator/go v0.0.0-20180806060727-1624edc4454b h1:X61dhFTE1Au92SvyF8HyAwdjWqiSdfBgFR7wTxC0+uU=
+github.com/json-iterator/go v0.0.0-20180806060727-1624edc4454b/go.mod h1:+SdeFBvtyEkXs7REEP0seUULqWtbJapLOCVDaaPEHmU=
+github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
+github.com/manucorporat/stats v0.0.0-20180402194714-3ba42d56d227 h1:KIaAZ/V+/0/6BOULrmBQ9T1ed8BkKqGIjIKW923nJuo=
+github.com/manucorporat/stats v0.0.0-20180402194714-3ba42d56d227/go.mod h1:ruMr5t05gVho4tuDv0PbI0Bb8nOxc/5Y6JzRHe/yfA0=
+github.com/mattn/go-isatty v0.0.3 h1:ns/ykhmWi7G9O+8a448SecJU3nSMBXJfqQkl0upE1jI=
+github.com/mattn/go-isatty v0.0.3/go.mod h1:M+lRXTBqGeGNdLjl/ufCoiOlB5xdOkqRJdNxMWT7Zi4=
+github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd h1:TRLaZ9cD/w8PVh93nsPXa1VrQ6jlwL5oN8l14QlcNfg=
+github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
+github.com/modern-go/reflect2 v1.0.1 h1:9f412s+6RmYXLWZSEzVVgPGK7C2PphHj5RJrvfx9AWI=
+github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
+github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+github.com/thinkerou/favicon v0.0.0-20170710140520-94a442a49da6 h1:d/LEgOfWe+AlOCz/kzmkvlO+gq9LRGhjSHqt2nx8Muc=
+github.com/thinkerou/favicon v0.0.0-20170710140520-94a442a49da6/go.mod h1:HL7Pap5kOluZv1ku34pZo/AJ44GaxMEPFZ3pmuexV2s=
+github.com/ugorji/go v1.1.1 h1:gmervu+jDMvXTbcHQ0pd2wee85nEoE0BsVyEuzkfK8w=
+github.com/ugorji/go v1.1.1/go.mod h1:hnLbHMwcvSihnDhEfx2/BzKp2xb0Y+ErdfYcrs9tkJQ=
+golang.org/x/crypto v0.0.0-20180910181607-0e37d006457b h1:2b9XGzhjiYsYPnKXoEfL7klWZQIt8IfyRCz62gCqqlQ=
+golang.org/x/crypto v0.0.0-20180910181607-0e37d006457b/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
+golang.org/x/lint v0.0.0-20180702182130-06c8688daad7/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=
+golang.org/x/net v0.0.0-20180826012351-8a410e7b638d h1:g9qWBGx4puODJTMVyoPrpoxPFgVGd+z1DZwjfRu4d0I=
+golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
+golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f h1:wMNYb4v58l5UBM7MYRLPG6ZhfOqbKu7X5eyFl8ZhKvA=
+golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e h1:o3PsSEY8E4eXWkXrIP9YJALUkVZqzHJT5DOasTyn8Vs=
+golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/tools v0.0.0-20180828015842-6cd1fcedba52/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
+google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8 h1:Nw54tB0rB7hY/N0NQvRW8DG4Yk3Q6T9cu9RcFQDu1tc=
+google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
+google.golang.org/grpc v1.15.0 h1:Az/KuahOM4NAidTEuJCv/RonAA7rYsTPkqXVjr+8OOw=
+google.golang.org/grpc v1.15.0/go.mod h1:0JHn/cJsOMiMfNA9+DeHDlAU7KAAB5GDlYFpa9MZMio=
+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/go-playground/assert.v1 v1.2.1 h1:xoYuJVE7KT85PYWrN730RguIQO0ePzVRfFMXadIrXTM=
+gopkg.in/go-playground/assert.v1 v1.2.1/go.mod h1:9RXL0bg/zibRAgZUYszZSwO/z8Y/a8bDuhia5mkpMnE=
+gopkg.in/go-playground/validator.v8 v8.18.2 h1:lFB4DoMU6B626w8ny76MV7VX6W2VHct2GVOI3xgiMrQ=
+gopkg.in/go-playground/validator.v8 v8.18.2/go.mod h1:RX2a/7Ha8BgOhfk7j780h4/u/RRjR0eouCJSH80/M2Y=
+gopkg.in/yaml.v2 v2.2.1 h1:mUhvW9EsL+naU5Q3cakzfE91YhliOondGd6ZrsDBHQE=
+gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+honnef.co/go/tools v0.0.0-20180728063816-88497007e858/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
diff --git a/internal/json/json.go b/internal/json/json.go
index 4f643c56..419d35f2 100644
--- a/internal/json/json.go
+++ b/internal/json/json.go
@@ -9,8 +9,12 @@ package json
 import "encoding/json"
 
 var (
-	Marshal       = json.Marshal
+	// Marshal is exported by gin/json package.
+	Marshal = json.Marshal
+	// MarshalIndent is exported by gin/json package.
 	MarshalIndent = json.MarshalIndent
-	NewDecoder    = json.NewDecoder
-	NewEncoder    = json.NewEncoder
+	// NewDecoder is exported by gin/json package.
+	NewDecoder = json.NewDecoder
+	// NewEncoder is exported by gin/json package.
+	NewEncoder = json.NewEncoder
 )
diff --git a/internal/json/jsoniter.go b/internal/json/jsoniter.go
index f1ed5bea..2021c53c 100644
--- a/internal/json/jsoniter.go
+++ b/internal/json/jsoniter.go
@@ -9,9 +9,13 @@ package json
 import "github.com/json-iterator/go"
 
 var (
-	json          = jsoniter.ConfigCompatibleWithStandardLibrary
-	Marshal       = json.Marshal
+	json = jsoniter.ConfigCompatibleWithStandardLibrary
+	// Marshal is exported by gin/json package.
+	Marshal = json.Marshal
+	// MarshalIndent is exported by gin/json package.
 	MarshalIndent = json.MarshalIndent
-	NewDecoder    = json.NewDecoder
-	NewEncoder    = json.NewEncoder
+	// NewDecoder is exported by gin/json package.
+	NewDecoder = json.NewDecoder
+	// NewEncoder is exported by gin/json package.
+	NewEncoder = json.NewEncoder
 )
diff --git a/mode.go b/mode.go
index 9df4e45f..7cb0143a 100644
--- a/mode.go
+++ b/mode.go
@@ -11,12 +11,16 @@ import (
 	"github.com/gin-gonic/gin/binding"
 )
 
+// ENV_GIN_MODE indicates environment name for gin mode.
 const ENV_GIN_MODE = "GIN_MODE"
 
 const (
-	DebugMode   = "debug"
+	// DebugMode indicates gin mode is debug.
+	DebugMode = "debug"
+	// ReleaseMode indicates gin mode is relase.
 	ReleaseMode = "release"
-	TestMode    = "test"
+	// TestMode indicates gin mode is test.
+	TestMode = "test"
 )
 const (
 	debugCode = iota
@@ -42,6 +46,7 @@ func init() {
 	SetMode(mode)
 }
 
+// SetMode sets gin mode according to input string.
 func SetMode(value string) {
 	switch value {
 	case DebugMode, "":
@@ -59,14 +64,18 @@ func SetMode(value string) {
 	modeName = value
 }
 
+// DisableBindValidation closes the default validator.
 func DisableBindValidation() {
 	binding.Validator = nil
 }
 
+// EnableJsonDecoderUseNumber sets true for binding.EnableDecoderUseNumberto to
+// call the UseNumber method on the JSON Decoder instance.
 func EnableJsonDecoderUseNumber() {
 	binding.EnableDecoderUseNumber = true
 }
 
+// Mode returns currently gin mode.
 func Mode() string {
 	return modeName
 }
diff --git a/render/data.go b/render/data.go
index 33194913..6ba657ba 100644
--- a/render/data.go
+++ b/render/data.go
@@ -6,6 +6,7 @@ package render
 
 import "net/http"
 
+// Data contains ContentType and bytes data.
 type Data struct {
 	ContentType string
 	Data        []byte
@@ -18,6 +19,7 @@ func (r Data) Render(w http.ResponseWriter) (err error) {
 	return
 }
 
+// WriteContentType (Data) writes custom ContentType.
 func (r Data) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, []string{r.ContentType})
 }
diff --git a/render/html.go b/render/html.go
index 1e3be65b..6696ece9 100644
--- a/render/html.go
+++ b/render/html.go
@@ -9,20 +9,27 @@ import (
 	"net/http"
 )
 
+// Delims represents a set of Left and Right delimiters for HTML template rendering.
 type Delims struct {
-	Left  string
+	// Left delimiter, defaults to {{.
+	Left string
+	// Right delimiter, defaults to }}.
 	Right string
 }
 
+// HTMLRender interface is to be implemented by HTMLProduction and HTMLDebug.
 type HTMLRender interface {
+	// Instance returns an HTML instance.
 	Instance(string, interface{}) Render
 }
 
+// HTMLProduction contains template reference and its delims.
 type HTMLProduction struct {
 	Template *template.Template
 	Delims   Delims
 }
 
+// HTMLDebug contains template delims and pattern and function with file list.
 type HTMLDebug struct {
 	Files   []string
 	Glob    string
@@ -30,6 +37,7 @@ type HTMLDebug struct {
 	FuncMap template.FuncMap
 }
 
+// HTML contains template reference and its name with given interface object.
 type HTML struct {
 	Template *template.Template
 	Name     string
@@ -38,6 +46,7 @@ type HTML struct {
 
 var htmlContentType = []string{"text/html; charset=utf-8"}
 
+// Instance (HTMLProduction) returns an HTML instance which it realizes Render interface.
 func (r HTMLProduction) Instance(name string, data interface{}) Render {
 	return HTML{
 		Template: r.Template,
@@ -46,6 +55,7 @@ func (r HTMLProduction) Instance(name string, data interface{}) Render {
 	}
 }
 
+// Instance (HTMLDebug) returns an HTML instance which it realizes Render interface.
 func (r HTMLDebug) Instance(name string, data interface{}) Render {
 	return HTML{
 		Template: r.loadTemplate(),
@@ -66,6 +76,7 @@ func (r HTMLDebug) loadTemplate() *template.Template {
 	panic("the HTML debug render was created without files or glob pattern")
 }
 
+// Render (HTML) executes template and writes its result with custom ContentType for response.
 func (r HTML) Render(w http.ResponseWriter) error {
 	r.WriteContentType(w)
 
@@ -75,6 +86,7 @@ func (r HTML) Render(w http.ResponseWriter) error {
 	return r.Template.ExecuteTemplate(w, r.Name, r.Data)
 }
 
+// WriteContentType (HTML) writes HTML ContentType.
 func (r HTML) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, htmlContentType)
 }
diff --git a/render/json.go b/render/json.go
index f6b7878e..32d0fc42 100644
--- a/render/json.go
+++ b/render/json.go
@@ -13,34 +13,41 @@ import (
 	"github.com/gin-gonic/gin/internal/json"
 )
 
+// JSON contains the given interface object.
 type JSON struct {
 	Data interface{}
 }
 
+// IndentedJSON contains the given interface object.
 type IndentedJSON struct {
 	Data interface{}
 }
 
+// SecureJSON contains the given interface object and its prefix.
 type SecureJSON struct {
 	Prefix string
 	Data   interface{}
 }
 
+// JsonpJSON contains the given interface object its callback.
 type JsonpJSON struct {
 	Callback string
 	Data     interface{}
 }
 
+// AsciiJSON contains the given interface object.
 type AsciiJSON struct {
 	Data interface{}
 }
 
+// SecureJSONPrefix is a string which represents SecureJSON prefix.
 type SecureJSONPrefix string
 
 var jsonContentType = []string{"application/json; charset=utf-8"}
 var jsonpContentType = []string{"application/javascript; charset=utf-8"}
 var jsonAsciiContentType = []string{"application/json"}
 
+// Render (JSON) writes data with custom ContentType.
 func (r JSON) Render(w http.ResponseWriter) (err error) {
 	if err = WriteJSON(w, r.Data); err != nil {
 		panic(err)
@@ -48,10 +55,12 @@ func (r JSON) Render(w http.ResponseWriter) (err error) {
 	return
 }
 
+// WriteContentType (JSON) writes JSON ContentType.
 func (r JSON) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, jsonContentType)
 }
 
+// WriteJSON marshals the given interface object and writes it with custom ContentType.
 func WriteJSON(w http.ResponseWriter, obj interface{}) error {
 	writeContentType(w, jsonContentType)
 	jsonBytes, err := json.Marshal(obj)
@@ -62,6 +71,7 @@ func WriteJSON(w http.ResponseWriter, obj interface{}) error {
 	return nil
 }
 
+// Render (IndentedJSON) marshals the given interface object and writes it with custom ContentType.
 func (r IndentedJSON) Render(w http.ResponseWriter) error {
 	r.WriteContentType(w)
 	jsonBytes, err := json.MarshalIndent(r.Data, "", "    ")
@@ -72,10 +82,12 @@ func (r IndentedJSON) Render(w http.ResponseWriter) error {
 	return nil
 }
 
+// WriteContentType (IndentedJSON) writes JSON ContentType.
 func (r IndentedJSON) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, jsonContentType)
 }
 
+// Render (SecureJSON) marshals the given interface object and writes it with custom ContentType.
 func (r SecureJSON) Render(w http.ResponseWriter) error {
 	r.WriteContentType(w)
 	jsonBytes, err := json.Marshal(r.Data)
@@ -90,10 +102,12 @@ func (r SecureJSON) Render(w http.ResponseWriter) error {
 	return nil
 }
 
+// WriteContentType (SecureJSON) writes JSON ContentType.
 func (r SecureJSON) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, jsonContentType)
 }
 
+// Render (JsonpJSON) marshals the given interface object and writes it and its callback with custom ContentType.
 func (r JsonpJSON) Render(w http.ResponseWriter) (err error) {
 	r.WriteContentType(w)
 	ret, err := json.Marshal(r.Data)
@@ -115,10 +129,12 @@ func (r JsonpJSON) Render(w http.ResponseWriter) (err error) {
 	return nil
 }
 
+// WriteContentType (JsonpJSON) writes Javascript ContentType.
 func (r JsonpJSON) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, jsonpContentType)
 }
 
+// Render (AsciiJSON) marshals the given interface object and writes it with custom ContentType.
 func (r AsciiJSON) Render(w http.ResponseWriter) (err error) {
 	r.WriteContentType(w)
 	ret, err := json.Marshal(r.Data)
@@ -139,6 +155,7 @@ func (r AsciiJSON) Render(w http.ResponseWriter) (err error) {
 	return nil
 }
 
+// WriteContentType (AsciiJSON) writes JSON ContentType.
 func (r AsciiJSON) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, jsonAsciiContentType)
 }
diff --git a/render/json_17.go b/render/json_17.go
index 75f7f374..208193c7 100644
--- a/render/json_17.go
+++ b/render/json_17.go
@@ -12,10 +12,12 @@ import (
 	"github.com/gin-gonic/gin/internal/json"
 )
 
+// PureJSON contains the given interface object.
 type PureJSON struct {
 	Data interface{}
 }
 
+// Render (PureJSON) writes custom ContentType and encodes the given interface object.
 func (r PureJSON) Render(w http.ResponseWriter) error {
 	r.WriteContentType(w)
 	encoder := json.NewEncoder(w)
@@ -23,6 +25,7 @@ func (r PureJSON) Render(w http.ResponseWriter) error {
 	return encoder.Encode(r.Data)
 }
 
+// WriteContentType (PureJSON) writes custom ContentType.
 func (r PureJSON) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, jsonContentType)
 }
diff --git a/render/msgpack.go b/render/msgpack.go
index b6b8aa0f..dc681fcf 100644
--- a/render/msgpack.go
+++ b/render/msgpack.go
@@ -10,20 +10,24 @@ import (
 	"github.com/ugorji/go/codec"
 )
 
+// MsgPack contains the given interface object.
 type MsgPack struct {
 	Data interface{}
 }
 
 var msgpackContentType = []string{"application/msgpack; charset=utf-8"}
 
+// WriteContentType (MsgPack) writes MsgPack ContentType.
 func (r MsgPack) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, msgpackContentType)
 }
 
+// Render (MsgPack) encodes the given interface object and writes data with custom ContentType.
 func (r MsgPack) Render(w http.ResponseWriter) error {
 	return WriteMsgPack(w, r.Data)
 }
 
+// WriteMsgPack writes MsgPack ContentType and encodes the given interface object.
 func WriteMsgPack(w http.ResponseWriter, obj interface{}) error {
 	writeContentType(w, msgpackContentType)
 	var mh codec.MsgpackHandle
diff --git a/render/protobuf.go b/render/protobuf.go
index 34f1e9b5..47895072 100644
--- a/render/protobuf.go
+++ b/render/protobuf.go
@@ -10,12 +10,14 @@ import (
 	"github.com/golang/protobuf/proto"
 )
 
+// ProtoBuf contains the given interface object.
 type ProtoBuf struct {
 	Data interface{}
 }
 
 var protobufContentType = []string{"application/x-protobuf"}
 
+// Render (ProtoBuf) marshals the given interface object and writes data with custom ContentType.
 func (r ProtoBuf) Render(w http.ResponseWriter) error {
 	r.WriteContentType(w)
 
@@ -28,6 +30,7 @@ func (r ProtoBuf) Render(w http.ResponseWriter) error {
 	return nil
 }
 
+// WriteContentType (ProtoBuf) writes ProtoBuf ContentType.
 func (r ProtoBuf) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, protobufContentType)
 }
diff --git a/render/reader.go b/render/reader.go
index 7a06cce4..ab60e53a 100644
--- a/render/reader.go
+++ b/render/reader.go
@@ -10,6 +10,7 @@ import (
 	"strconv"
 )
 
+// Reader contains the IO reader and its length, and custom ContentType and other headers.
 type Reader struct {
 	ContentType   string
 	ContentLength int64
@@ -26,10 +27,12 @@ func (r Reader) Render(w http.ResponseWriter) (err error) {
 	return
 }
 
+// WriteContentType (Reader) writes custom ContentType.
 func (r Reader) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, []string{r.ContentType})
 }
 
+// writeHeaders writes custom Header.
 func (r Reader) writeHeaders(w http.ResponseWriter, headers map[string]string) {
 	header := w.Header()
 	for k, v := range headers {
diff --git a/render/redirect.go b/render/redirect.go
index a0634f5a..9c145fe2 100644
--- a/render/redirect.go
+++ b/render/redirect.go
@@ -9,12 +9,14 @@ import (
 	"net/http"
 )
 
+// Redirect contains the http request reference and redirects status code and location.
 type Redirect struct {
 	Code     int
 	Request  *http.Request
 	Location string
 }
 
+// Render (Redirect) redirects the http request to new location and writes redirect response.
 func (r Redirect) Render(w http.ResponseWriter) error {
 	// todo(thinkerou): go1.6 not support StatusPermanentRedirect(308)
 	// when we upgrade go version we can use http.StatusPermanentRedirect
@@ -25,4 +27,5 @@ func (r Redirect) Render(w http.ResponseWriter) error {
 	return nil
 }
 
+// WriteContentType (Redirect) don't write any ContentType.
 func (r Redirect) WriteContentType(http.ResponseWriter) {}
diff --git a/render/render.go b/render/render.go
index df0d1d7c..abfc79fc 100644
--- a/render/render.go
+++ b/render/render.go
@@ -6,8 +6,11 @@ package render
 
 import "net/http"
 
+// Render interface is to be implemented by JSON, XML, HTML, YAML and so on.
 type Render interface {
+	// Render writes data with custom ContentType.
 	Render(http.ResponseWriter) error
+	// WriteContentType writes custom ContentType.
 	WriteContentType(w http.ResponseWriter)
 }
 
diff --git a/render/render_test.go b/render/render_test.go
index fe9228e9..09ccc658 100644
--- a/render/render_test.go
+++ b/render/render_test.go
@@ -287,7 +287,7 @@ func TestRenderProtoBuf(t *testing.T) {
 	err = (ProtoBuf{data}).Render(w)
 
 	assert.NoError(t, err)
-	assert.Equal(t, string(protoData[:]), w.Body.String())
+	assert.Equal(t, string(protoData), w.Body.String())
 	assert.Equal(t, "application/x-protobuf", w.Header().Get("Content-Type"))
 }
 
diff --git a/render/text.go b/render/text.go
index 7a6acc44..2ea7343c 100644
--- a/render/text.go
+++ b/render/text.go
@@ -10,6 +10,7 @@ import (
 	"net/http"
 )
 
+// String contains the given interface object slice and its format.
 type String struct {
 	Format string
 	Data   []interface{}
@@ -17,15 +18,18 @@ type String struct {
 
 var plainContentType = []string{"text/plain; charset=utf-8"}
 
+// Render (String) writes data with custom ContentType.
 func (r String) Render(w http.ResponseWriter) error {
 	WriteString(w, r.Format, r.Data)
 	return nil
 }
 
+// WriteContentType (String) writes Plain ContentType.
 func (r String) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, plainContentType)
 }
 
+// WriteString writes data according to its format and write custom ContentType.
 func WriteString(w http.ResponseWriter, format string, data []interface{}) {
 	writeContentType(w, plainContentType)
 	if len(data) > 0 {
diff --git a/render/xml.go b/render/xml.go
index cff1ac3e..cc5390a2 100644
--- a/render/xml.go
+++ b/render/xml.go
@@ -9,17 +9,20 @@ import (
 	"net/http"
 )
 
+// XML contains the given interface object.
 type XML struct {
 	Data interface{}
 }
 
 var xmlContentType = []string{"application/xml; charset=utf-8"}
 
+// Render (XML) encodes the given interface object and writes data with custom ContentType.
 func (r XML) Render(w http.ResponseWriter) error {
 	r.WriteContentType(w)
 	return xml.NewEncoder(w).Encode(r.Data)
 }
 
+// WriteContentType (XML) writes XML ContentType for response.
 func (r XML) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, xmlContentType)
 }
diff --git a/render/yaml.go b/render/yaml.go
index 25d0ebd4..33bc3254 100644
--- a/render/yaml.go
+++ b/render/yaml.go
@@ -10,12 +10,14 @@ import (
 	"gopkg.in/yaml.v2"
 )
 
+// YAML contains the given interface object.
 type YAML struct {
 	Data interface{}
 }
 
 var yamlContentType = []string{"application/x-yaml; charset=utf-8"}
 
+// Render (YAML) marshals the given interface object and writes data with custom ContentType.
 func (r YAML) Render(w http.ResponseWriter) error {
 	r.WriteContentType(w)
 
@@ -28,6 +30,7 @@ func (r YAML) Render(w http.ResponseWriter) error {
 	return nil
 }
 
+// WriteContentType (YAML) writes YAML ContentType for response.
 func (r YAML) WriteContentType(w http.ResponseWriter) {
 	writeContentType(w, yamlContentType)
 }
diff --git a/routergroup.go b/routergroup.go
index 876a61b8..579aa7dc 100644
--- a/routergroup.go
+++ b/routergroup.go
@@ -11,11 +11,13 @@ import (
 	"strings"
 )
 
+// IRouter defines all router handle interface includes single and group router.
 type IRouter interface {
 	IRoutes
 	Group(string, ...HandlerFunc) *RouterGroup
 }
 
+// IRoutes defines all router handle interface.
 type IRoutes interface {
 	Use(...HandlerFunc) IRoutes
 
@@ -34,8 +36,8 @@ type IRoutes interface {
 	StaticFS(string, http.FileSystem) IRoutes
 }
 
-// RouterGroup is used internally to configure router, a RouterGroup is associated with a prefix
-// and an array of handlers (middleware).
+// RouterGroup is used internally to configure router, a RouterGroup is associated with
+// a prefix and an array of handlers (middleware).
 type RouterGroup struct {
 	Handlers HandlersChain
 	basePath string
@@ -61,6 +63,8 @@ func (group *RouterGroup) Group(relativePath string, handlers ...HandlerFunc) *R
 	}
 }
 
+// BasePath returns the base path of router group.
+// For example, if v := router.Group("/rest/n/v1/api"), v.BasePath() is "/rest/n/v1/api".
 func (group *RouterGroup) BasePath() string {
 	return group.basePath
 }
diff --git a/tree.go b/tree.go
index b6530665..ada62ceb 100644
--- a/tree.go
+++ b/tree.go
@@ -193,9 +193,16 @@ func (n *node) addRoute(path string, handlers HandlersChain) {
 						}
 					}
 
-					panic("path segment '" + path +
+					pathSeg := path
+					if n.nType != catchAll {
+						pathSeg = strings.SplitN(path, "/", 2)[0]
+					}
+					prefix := fullPath[:strings.Index(fullPath, pathSeg)] + n.path
+					panic("'" + pathSeg +
+						"' in new path '" + fullPath +
 						"' conflicts with existing wildcard '" + n.path +
-						"' in path '" + fullPath + "'")
+						"' in existing prefix '" + prefix +
+						"'")
 				}
 
 				c := path[0]
diff --git a/tree_test.go b/tree_test.go
index 5bc27171..a1b3bbe7 100644
--- a/tree_test.go
+++ b/tree_test.go
@@ -5,7 +5,9 @@
 package gin
 
 import (
+	"fmt"
 	"reflect"
+	"regexp"
 	"strings"
 	"testing"
 )
@@ -125,8 +127,6 @@ func TestTreeAddAndGet(t *testing.T) {
 		tree.addRoute(route, fakeHandler(route))
 	}
 
-	//printChildren(tree, "")
-
 	checkRequests(t, tree, testRequests{
 		{"/a", false, "/a", nil},
 		{"/", true, "", nil},
@@ -168,8 +168,6 @@ func TestTreeWildcard(t *testing.T) {
 		tree.addRoute(route, fakeHandler(route))
 	}
 
-	//printChildren(tree, "")
-
 	checkRequests(t, tree, testRequests{
 		{"/", false, "/", nil},
 		{"/cmd/test/", false, "/cmd/:tool/", Params{Param{"tool", "test"}}},
@@ -208,7 +206,6 @@ func TestUnescapeParameters(t *testing.T) {
 		tree.addRoute(route, fakeHandler(route))
 	}
 
-	//printChildren(tree, "")
 	unescape := true
 	checkRequests(t, tree, testRequests{
 		{"/", false, "/", nil},
@@ -260,8 +257,6 @@ func testRoutes(t *testing.T, routes []testRoute) {
 			t.Errorf("unexpected panic for route '%s': %v", route.path, recv)
 		}
 	}
-
-	//printChildren(tree, "")
 }
 
 func TestTreeWildcardConflict(t *testing.T) {
@@ -328,8 +323,6 @@ func TestTreeDupliatePath(t *testing.T) {
 		}
 	}
 
-	//printChildren(tree, "")
-
 	checkRequests(t, tree, testRequests{
 		{"/", false, "/", nil},
 		{"/doc/", false, "/doc/", nil},
@@ -444,8 +437,6 @@ func TestTreeTrailingSlashRedirect(t *testing.T) {
 		}
 	}
 
-	//printChildren(tree, "")
-
 	tsrRoutes := [...]string{
 		"/hi/",
 		"/b",
@@ -664,3 +655,43 @@ func TestTreeInvalidNodeType(t *testing.T) {
 		t.Fatalf("Expected panic '"+panicMsg+"', got '%v'", recv)
 	}
 }
+
+func TestTreeWildcardConflictEx(t *testing.T) {
+	conflicts := [...]struct {
+		route        string
+		segPath      string
+		existPath    string
+		existSegPath string
+	}{
+		{"/who/are/foo", "/foo", `/who/are/\*you`, `/\*you`},
+		{"/who/are/foo/", "/foo/", `/who/are/\*you`, `/\*you`},
+		{"/who/are/foo/bar", "/foo/bar", `/who/are/\*you`, `/\*you`},
+		{"/conxxx", "xxx", `/con:tact`, `:tact`},
+		{"/conooo/xxx", "ooo", `/con:tact`, `:tact`},
+	}
+
+	for _, conflict := range conflicts {
+		// I have to re-create a 'tree', because the 'tree' will be
+		// in an inconsistent state when the loop recovers from the
+		// panic which threw by 'addRoute' function.
+		tree := &node{}
+		routes := [...]string{
+			"/con:tact",
+			"/who/are/*you",
+			"/who/foo/hello",
+		}
+
+		for _, route := range routes {
+			tree.addRoute(route, fakeHandler(route))
+		}
+
+		recv := catchPanic(func() {
+			tree.addRoute(conflict.route, fakeHandler(conflict.route))
+		})
+
+		if !regexp.MustCompile(fmt.Sprintf("'%s' in new path .* conflicts with existing wildcard '%s' in existing prefix '%s'",
+			conflict.segPath, conflict.existSegPath, conflict.existPath)).MatchString(fmt.Sprint(recv)) {
+			t.Fatalf("invalid wildcard conflict error (%v)", recv)
+		}
+	}
+}
diff --git a/utils.go b/utils.go
index bf32c775..f4532d56 100644
--- a/utils.go
+++ b/utils.go
@@ -14,8 +14,10 @@ import (
 	"strings"
 )
 
+// BindKey indicates a default bind key.
 const BindKey = "_gin-gonic/gin/bindkey"
 
+// Bind is a helper function for given interface object and returns a Gin middleware.
 func Bind(val interface{}) HandlerFunc {
 	value := reflect.ValueOf(val)
 	if value.Kind() == reflect.Ptr {
@@ -33,16 +35,14 @@ func Bind(val interface{}) HandlerFunc {
 	}
 }
 
-// WrapF is a helper function for wrapping http.HandlerFunc
-// Returns a Gin middleware
+// WrapF is a helper function for wrapping http.HandlerFunc and returns a Gin middleware.
 func WrapF(f http.HandlerFunc) HandlerFunc {
 	return func(c *Context) {
 		f(c.Writer, c.Request)
 	}
 }
 
-// WrapH is a helper function for wrapping http.Handler
-// Returns a Gin middleware
+// WrapH is a helper function for wrapping http.Handler and returns a Gin middleware.
 func WrapH(h http.Handler) HandlerFunc {
 	return func(c *Context) {
 		h.ServeHTTP(c.Writer, c.Request)
diff --git a/vendor/vendor.json b/vendor/vendor.json
index e6d038a4..86df11be 100644
--- a/vendor/vendor.json
+++ b/vendor/vendor.json
@@ -27,8 +27,8 @@
 			"path": "github.com/json-iterator/go",
 			"revision": "1624edc4454b8682399def8740d46db5e4362ba4",
 			"revisionTime": "2018-08-06T06:07:27Z",
-			"version": "1.1.5",
-			"versionExact": "1.1.5"
+			"version": "v1.1",
+			"versionExact": "v1.1.5"
 		},
 		{
 			"checksumSHA1": "y/A5iuvwjytQE2CqVuphQRXR2nI=",
@@ -38,24 +38,6 @@
 			"version": "v0.0.3",
 			"versionExact": "v0.0.3"
 		},
-		{
-			"checksumSHA1": "ZTcgWKWHsrX0RXYVXn5Xeb8Q0go=",
-			"path": "github.com/modern-go/concurrent",
-			"revision": "bacd9c7ef1dd9b15be4a9909b8ac7a4e313eec94",
-			"revisionTime": "2018-03-06T01:26:44Z"
-		},
-		{
-			"checksumSHA1": "qvH48wzTIV3QKSDqI0dLFtVjaDI=",
-			"path": "github.com/modern-go/reflect2",
-			"revision": "94122c33edd36123c84d5368cfb2b69df93a0ec8",
-			"revisionTime": "2018-07-18T01:23:57Z"
-		},
-		{
-			"checksumSHA1": "LuFv4/jlrmFNnDb/5SCSEPAM9vU=",
-			"path": "github.com/pmezard/go-difflib/difflib",
-			"revision": "792786c7400a136282c1664665ae0a8db921c6c2",
-			"revisionTime": "2016-01-10T10:55:54Z"
-		},
 		{
 			"checksumSHA1": "c6pbpF7eowwO59phRTpF8cQ80Z0=",
 			"path": "github.com/stretchr/testify/assert",
@@ -79,12 +61,6 @@
 			"revision": "d4c55e66d8c3a2f3382d264b08e3e3454a66355a",
 			"revisionTime": "2016-10-18T08:54:36Z"
 		},
-		{
-			"checksumSHA1": "7Gocawl8bm27cpAILtuf21xvVD8=",
-			"path": "golang.org/x/sys/unix",
-			"revision": "1c9583448a9c3aa0f9a6a5241bf73c0bd8aafded",
-			"revisionTime": "2018-08-15T07:37:39Z"
-		},
 		{
 			"checksumSHA1": "P/k5ZGf0lEBgpKgkwy++F7K1PSg=",
 			"path": "gopkg.in/go-playground/validator.v8",
diff --git a/version.go b/version.go
new file mode 100644
index 00000000..028caebe
--- /dev/null
+++ b/version.go
@@ -0,0 +1,8 @@
+// Copyright 2018 Gin Core Team.  All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package gin
+
+// Version is the current gin framework's version.
+const Version = "v1.4.0-dev"