diff --git a/models/issue_assignees.go b/models/issue_assignees.go
index 577ed860f..05e1797c1 100644
--- a/models/issue_assignees.go
+++ b/models/issue_assignees.go
@@ -81,23 +81,6 @@ func isUserAssignedToIssue(e Engine, issue *Issue, user *User) (isAssigned bool,
 	return e.Get(&IssueAssignees{IssueID: issue.ID, AssigneeID: user.ID})
 }
 
-// MakeAssigneeList concats a string with all names of the assignees. Useful for logs.
-func MakeAssigneeList(issue *Issue) (assigneeList string, err error) {
-	err = issue.loadAssignees(x)
-	if err != nil {
-		return "", err
-	}
-
-	for in, assignee := range issue.Assignees {
-		assigneeList += assignee.Name
-
-		if len(issue.Assignees) > (in + 1) {
-			assigneeList += ", "
-		}
-	}
-	return
-}
-
 // ClearAssigneeByUserID deletes all assignments of an user
 func clearAssigneeByUserID(sess *xorm.Session, userID int64) (err error) {
 	_, err = sess.Delete(&IssueAssignees{AssigneeID: userID})
diff --git a/models/update.go b/models/update.go
index 8e18450db..421c44bb4 100644
--- a/models/update.go
+++ b/models/update.go
@@ -9,20 +9,6 @@ import (
 	"strings"
 )
 
-// PushUpdateDeleteTags updates a number of delete tags
-func PushUpdateDeleteTags(repo *Repository, tags []string) error {
-	sess := x.NewSession()
-	defer sess.Close()
-	if err := sess.Begin(); err != nil {
-		return fmt.Errorf("Unable to begin sess in PushUpdateDeleteTags: %v", err)
-	}
-	if err := pushUpdateDeleteTags(sess, repo, tags); err != nil {
-		return err
-	}
-
-	return sess.Commit()
-}
-
 // PushUpdateDeleteTagsContext updates a number of delete tags with context
 func PushUpdateDeleteTagsContext(ctx DBContext, repo *Repository, tags []string) error {
 	return pushUpdateDeleteTags(ctx.e, repo, tags)
diff --git a/models/user.go b/models/user.go
index 30ede2373..f91ffa716 100644
--- a/models/user.go
+++ b/models/user.go
@@ -1315,21 +1315,6 @@ func UserPath(userName string) string {
 	return filepath.Join(setting.RepoRootPath, strings.ToLower(userName))
 }
 
-// GetUserByKeyID get user information by user's public key id
-func GetUserByKeyID(keyID int64) (*User, error) {
-	var user User
-	has, err := x.Join("INNER", "public_key", "`public_key`.owner_id = `user`.id").
-		Where("`public_key`.id=?", keyID).
-		Get(&user)
-	if err != nil {
-		return nil, err
-	}
-	if !has {
-		return nil, ErrUserNotExist{0, "", keyID}
-	}
-	return &user, nil
-}
-
 func getUserByID(e Engine, id int64) (*User, error) {
 	u := new(User)
 	has, err := e.ID(id).Get(u)
diff --git a/modules/base/tool.go b/modules/base/tool.go
index cb9b99614..86606c8be 100644
--- a/modules/base/tool.go
+++ b/modules/base/tool.go
@@ -6,13 +6,11 @@ package base
 
 import (
 	"crypto/md5"
-	"crypto/rand"
 	"crypto/sha1"
 	"crypto/sha256"
 	"encoding/base64"
 	"encoding/hex"
 	"fmt"
-	"io"
 	"net/http"
 	"net/url"
 	"os"
@@ -75,18 +73,6 @@ func BasicAuthEncode(username, password string) string {
 	return base64.StdEncoding.EncodeToString([]byte(username + ":" + password))
 }
 
-// GetRandomBytesAsBase64 generates a random base64 string from n bytes
-func GetRandomBytesAsBase64(n int) string {
-	bytes := make([]byte, 32)
-	_, err := io.ReadFull(rand.Reader, bytes)
-
-	if err != nil {
-		log.Fatal("Error reading random bytes: %v", err)
-	}
-
-	return base64.RawURLEncoding.EncodeToString(bytes)
-}
-
 // VerifyTimeLimitCode verify time limit code
 func VerifyTimeLimitCode(data string, minutes int, code string) bool {
 	if len(code) <= 18 {
diff --git a/modules/structs/user_app.go b/modules/structs/user_app.go
index a0b0c3cb7..44df5a6a4 100644
--- a/modules/structs/user_app.go
+++ b/modules/structs/user_app.go
@@ -6,15 +6,9 @@
 package structs
 
 import (
-	"encoding/base64"
 	"time"
 )
 
-// BasicAuthEncode generate base64 of basic auth head
-func BasicAuthEncode(user, pass string) string {
-	return base64.StdEncoding.EncodeToString([]byte(user + ":" + pass))
-}
-
 // AccessToken represents an API access token.
 // swagger:response AccessToken
 type AccessToken struct {
diff --git a/modules/structs/utils.go b/modules/structs/utils.go
deleted file mode 100644
index aaeb653d0..000000000
--- a/modules/structs/utils.go
+++ /dev/null
@@ -1,20 +0,0 @@
-// Copyright 2015 The Gogs Authors. All rights reserved.
-// Use of this source code is governed by a MIT-style
-// license that can be found in the LICENSE file.
-
-package structs
-
-// Bool return address of bool value
-func Bool(v bool) *bool {
-	return &v
-}
-
-// String return address of string value
-func String(v string) *string {
-	return &v
-}
-
-// Int64 return address of int64 value
-func Int64(v int64) *int64 {
-	return &v
-}
diff --git a/modules/templates/helper.go b/modules/templates/helper.go
index a97431a69..9d3206934 100644
--- a/modules/templates/helper.go
+++ b/modules/templates/helper.go
@@ -437,31 +437,6 @@ func Sha1(str string) string {
 	return base.EncodeSha1(str)
 }
 
-// ReplaceLeft replaces all prefixes 'oldS' in 's' with 'newS'.
-func ReplaceLeft(s, oldS, newS string) string {
-	oldLen, newLen, i, n := len(oldS), len(newS), 0, 0
-	for ; i < len(s) && strings.HasPrefix(s[i:], oldS); n++ {
-		i += oldLen
-	}
-
-	// simple optimization
-	if n == 0 {
-		return s
-	}
-
-	// allocating space for the new string
-	curLen := n*newLen + len(s[i:])
-	replacement := make([]byte, curLen)
-
-	j := 0
-	for ; j < n*newLen; j += newLen {
-		copy(replacement[j:j+newLen], newS)
-	}
-
-	copy(replacement[j:], s[i:])
-	return string(replacement)
-}
-
 // RenderCommitMessage renders commit message with XSS-safe and special links.
 func RenderCommitMessage(msg, urlPrefix string, metas map[string]string) template.HTML {
 	return RenderCommitMessageLink(msg, urlPrefix, "", metas)
diff --git a/routers/api/v1/utils/utils.go b/routers/api/v1/utils/utils.go
index e02406d13..092ea3dbb 100644
--- a/routers/api/v1/utils/utils.go
+++ b/routers/api/v1/utils/utils.go
@@ -13,14 +13,6 @@ import (
 	"code.gitea.io/gitea/modules/convert"
 )
 
-// UserID user ID of authenticated user, or 0 if not authenticated
-func UserID(ctx *context.APIContext) int64 {
-	if ctx.User == nil {
-		return 0
-	}
-	return ctx.User.ID
-}
-
 // GetQueryBeforeSince return parsed time (unix format) from URL query's before and since
 func GetQueryBeforeSince(ctx *context.APIContext) (before, since int64, err error) {
 	qCreatedBefore := strings.Trim(ctx.Query("before"), " ")
diff --git a/routers/private/internal.go b/routers/private/internal.go
index b68a96c64..5bc01b0ae 100644
--- a/routers/private/internal.go
+++ b/routers/private/internal.go
@@ -8,7 +8,6 @@ package private
 import (
 	"strings"
 
-	"code.gitea.io/gitea/models"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/private"
 	"code.gitea.io/gitea/modules/setting"
@@ -27,55 +26,6 @@ func CheckInternalToken(ctx *macaron.Context) {
 	}
 }
 
-//GetRepositoryByOwnerAndName chainload to models.GetRepositoryByOwnerAndName
-func GetRepositoryByOwnerAndName(ctx *macaron.Context) {
-	//TODO use repo.Get(ctx *context.APIContext) ?
-	ownerName := ctx.Params(":owner")
-	repoName := ctx.Params(":repo")
-	repo, err := models.GetRepositoryByOwnerAndName(ownerName, repoName)
-	if err != nil {
-		ctx.JSON(500, map[string]interface{}{
-			"err": err.Error(),
-		})
-		return
-	}
-	ctx.JSON(200, repo)
-}
-
-//CheckUnitUser chainload to models.CheckUnitUser
-func CheckUnitUser(ctx *macaron.Context) {
-	repoID := ctx.ParamsInt64(":repoid")
-	userID := ctx.ParamsInt64(":userid")
-	repo, err := models.GetRepositoryByID(repoID)
-	if err != nil {
-		ctx.JSON(500, map[string]interface{}{
-			"err": err.Error(),
-		})
-		return
-	}
-
-	var user *models.User
-	if userID > 0 {
-		user, err = models.GetUserByID(userID)
-		if err != nil {
-			ctx.JSON(500, map[string]interface{}{
-				"err": err.Error(),
-			})
-			return
-		}
-	}
-
-	perm, err := models.GetUserRepoPermission(repo, user)
-	if err != nil {
-		ctx.JSON(500, map[string]interface{}{
-			"err": err.Error(),
-		})
-		return
-	}
-
-	ctx.JSON(200, perm.UnitAccessMode(models.UnitType(ctx.QueryInt("unitType"))))
-}
-
 // RegisterRoutes registers all internal APIs routes to web application.
 // These APIs will be invoked by internal commands for example `gitea serv` and etc.
 func RegisterRoutes(m *macaron.Macaron) {
diff --git a/services/pull/patch.go b/services/pull/patch.go
index 815263e89..96145fcd9 100644
--- a/services/pull/patch.go
+++ b/services/pull/patch.go
@@ -19,16 +19,6 @@ import (
 	"code.gitea.io/gitea/modules/log"
 )
 
-// DownloadDiff will write the patch for the pr to the writer
-func DownloadDiff(pr *models.PullRequest, w io.Writer, patch bool) error {
-	return DownloadDiffOrPatch(pr, w, false)
-}
-
-// DownloadPatch will write the patch for the pr to the writer
-func DownloadPatch(pr *models.PullRequest, w io.Writer, patch bool) error {
-	return DownloadDiffOrPatch(pr, w, true)
-}
-
 // DownloadDiffOrPatch will write the patch for the pr to the writer
 func DownloadDiffOrPatch(pr *models.PullRequest, w io.Writer, patch bool) error {
 	// Clone base repo.