diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index a71dad2674..4b36d51beb 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -829,6 +829,8 @@ patterns are available:
 
 - `java` suitable for source code in the Java language.
 
+- `kotlin` suitable for source code in the Kotlin language.
+
 - `markdown` suitable for Markdown documents.
 
 - `matlab` suitable for source code in the MATLAB and Octave languages.
diff --git a/t/t4018/kotlin-class b/t/t4018/kotlin-class
new file mode 100644
index 0000000000..bb864f22e6
--- /dev/null
+++ b/t/t4018/kotlin-class
@@ -0,0 +1,5 @@
+class RIGHT {
+	//comment
+	//comment
+	return ChangeMe
+}
diff --git a/t/t4018/kotlin-enum-class b/t/t4018/kotlin-enum-class
new file mode 100644
index 0000000000..8885f908fd
--- /dev/null
+++ b/t/t4018/kotlin-enum-class
@@ -0,0 +1,5 @@
+enum class RIGHT{
+	// Left
+	// a comment
+	ChangeMe
+}
diff --git a/t/t4018/kotlin-fun b/t/t4018/kotlin-fun
new file mode 100644
index 0000000000..2a60280256
--- /dev/null
+++ b/t/t4018/kotlin-fun
@@ -0,0 +1,5 @@
+fun RIGHT(){
+	//a comment
+	//b comment
+    return ChangeMe()
+}
diff --git a/t/t4018/kotlin-inheritace-class b/t/t4018/kotlin-inheritace-class
new file mode 100644
index 0000000000..77376c1f05
--- /dev/null
+++ b/t/t4018/kotlin-inheritace-class
@@ -0,0 +1,5 @@
+open class RIGHT{
+	// a comment
+	// b comment
+	// ChangeMe
+}
diff --git a/t/t4018/kotlin-inline-class b/t/t4018/kotlin-inline-class
new file mode 100644
index 0000000000..7bf46dd8d4
--- /dev/null
+++ b/t/t4018/kotlin-inline-class
@@ -0,0 +1,5 @@
+value class RIGHT(Args){
+	// a comment
+	// b comment
+	ChangeMe
+}
diff --git a/t/t4018/kotlin-interface b/t/t4018/kotlin-interface
new file mode 100644
index 0000000000..f686ba7770
--- /dev/null
+++ b/t/t4018/kotlin-interface
@@ -0,0 +1,5 @@
+interface RIGHT{
+	//another comment
+	//another comment
+	//ChangeMe
+}
diff --git a/t/t4018/kotlin-nested-fun b/t/t4018/kotlin-nested-fun
new file mode 100644
index 0000000000..12186858cb
--- /dev/null
+++ b/t/t4018/kotlin-nested-fun
@@ -0,0 +1,9 @@
+class LEFT{
+	class CENTER{
+		fun RIGHT(  a:Int){
+			//comment
+			//comment
+			ChangeMe
+		}
+	}
+}
diff --git a/t/t4018/kotlin-public-class b/t/t4018/kotlin-public-class
new file mode 100644
index 0000000000..9433fcc226
--- /dev/null
+++ b/t/t4018/kotlin-public-class
@@ -0,0 +1,5 @@
+public class RIGHT{
+	//comment1
+	//comment2
+	ChangeMe
+}
diff --git a/t/t4018/kotlin-sealed-class b/t/t4018/kotlin-sealed-class
new file mode 100644
index 0000000000..0efa4a4eaf
--- /dev/null
+++ b/t/t4018/kotlin-sealed-class
@@ -0,0 +1,5 @@
+sealed class RIGHT {
+	// a comment
+	// b comment
+	ChangeMe
+}
diff --git a/t/t4034-diff-words.sh b/t/t4034-diff-words.sh
index d5abcf4b4c..15764ee9ac 100755
--- a/t/t4034-diff-words.sh
+++ b/t/t4034-diff-words.sh
@@ -324,6 +324,7 @@ test_language_driver dts
 test_language_driver fortran
 test_language_driver html
 test_language_driver java
+test_language_driver kotlin
 test_language_driver matlab
 test_language_driver objc
 test_language_driver pascal
diff --git a/t/t4034/kotlin/expect b/t/t4034/kotlin/expect
new file mode 100644
index 0000000000..80eea3e386
--- /dev/null
+++ b/t/t4034/kotlin/expect
@@ -0,0 +1,33 @@
+<BOLD>diff --git a/pre b/post<RESET>
+<BOLD>index e8a199a..e6ebebb 100644<RESET>
+<BOLD>--- a/pre<RESET>
+<BOLD>+++ b/post<RESET>
+<CYAN>@@ -1,16 +1,16 @@<RESET>
+println("Hello World<RED>!\n<RESET><GREEN>?<RESET>")
+<GREEN>(<RESET>1<GREEN>) (<RESET>-1e10<RED>0xabcdef<RESET><GREEN>) (0xaybcdef)<RESET> '<RED>x<RESET><GREEN>y<RESET>'
+[<RED>a<RESET><GREEN>x<RESET>] <RED>a<RESET><GREEN>x<RESET>-><RED>b a<RESET><GREEN>y x<RESET>.<RED>b<RESET><GREEN>y<RESET>
+!<RED>a a<RESET><GREEN>x x<RESET>.inv() <RED>a<RESET><GREEN>x<RESET>*<RED>b a<RESET><GREEN>y x<RESET>&<RED>b<RESET>
+<RED>a<RESET><GREEN>y<RESET>
+<GREEN>x<RESET>*<RED>b a<RESET><GREEN>y x<RESET>/<RED>b a<RESET><GREEN>y x<RESET>%<RED>b<RESET>
+<RED>a<RESET><GREEN>y<RESET>
+<GREEN>x<RESET>+<RED>b a<RESET><GREEN>y x<RESET>-<RED>b<RESET>
+<RED>a<RESET><GREEN>y<RESET>
+<GREEN>x<RESET> shl <RED>b a<RESET><GREEN>y x<RESET> shr <RED>b<RESET>
+<RED>a<RESET><GREEN>y<RESET>
+<GREEN>x<RESET><<RED>b a<RESET><GREEN>y x<RESET><=<RED>b a<RESET><GREEN>y x<RESET>><RED>b a<RESET><GREEN>y x<RESET>>=<RED>b<RESET>
+<RED>a<RESET><GREEN>y<RESET>
+<GREEN>x<RESET>==<RED>b a<RESET><GREEN>y x<RESET>!=<RED>b a<RESET><GREEN>y x<RESET>===<RED>b<RESET>
+<RED>a and b<RESET>
+<RED>a<RESET><GREEN>y<RESET>
+<GREEN>x xnd y<RESET>
+<GREEN>x<RESET>^<RED>b<RESET>
+<RED>a<RESET><GREEN>y<RESET>
+<GREEN>x<RESET> or <RED>b<RESET>
+<RED>a<RESET><GREEN>y<RESET>
+<GREEN>x<RESET>&&<RED>b<RESET>
+<RED>a<RESET><GREEN>y<RESET>
+<GREEN>x<RESET>||<RED>b<RESET>
+<RED>a<RESET><GREEN>y<RESET>
+<GREEN>x<RESET>=<RED>b a<RESET><GREEN>y x<RESET>+=<RED>b a<RESET><GREEN>y x<RESET>-=<RED>b a<RESET><GREEN>y x<RESET>*=<RED>b a<RESET><GREEN>y x<RESET>/=<RED>b a<RESET><GREEN>y x<RESET>%=<RED>b a<RESET><GREEN>y x<RESET><<=<RED>b a<RESET><GREEN>y x<RESET>>>=<RED>b a<RESET><GREEN>y x<RESET>&=<RED>b a<RESET><GREEN>y x<RESET>^=<RED>b a<RESET><GREEN>y x<RESET>|=<RED>b<RESET>
+<RED>a<RESET><GREEN>y<RESET>
+<GREEN>x<RESET>,y
diff --git a/t/t4034/kotlin/post b/t/t4034/kotlin/post
new file mode 100644
index 0000000000..e6ebebb5e9
--- /dev/null
+++ b/t/t4034/kotlin/post
@@ -0,0 +1,16 @@
+println("Hello World?")
+(1) (-1e10) (0xaybcdef) 'y'
+[x] x->y x.y
+!x x.inv() x*y x&y
+x*y x/y x%y
+x+y x-y
+x shl y x shr y
+x<y x<=y x>y x>=y
+x==y x!=y x===y
+x xnd y
+x^y
+x or y
+x&&y
+x||y
+x=y x+=y x-=y x*=y x/=y x%=y x<<=y x>>=y x&=y x^=y x|=y
+x,y
diff --git a/t/t4034/kotlin/pre b/t/t4034/kotlin/pre
new file mode 100644
index 0000000000..e8a199adb0
--- /dev/null
+++ b/t/t4034/kotlin/pre
@@ -0,0 +1,16 @@
+println("Hello World!\n")
+1 -1e10 0xabcdef 'x'
+[a] a->b a.b
+!a a.inv() a*b a&b
+a*b a/b a%b
+a+b a-b
+a shl b a shr b
+a<b a<=b a>b a>=b
+a==b a!=b a===b
+a and b
+a^b
+a or b
+a&&b
+a||b
+a=b a+=b a-=b a*=b a/=b a%=b a<<=b a>>=b a&=b a^=b a|=b
+a,y
diff --git a/userdiff.c b/userdiff.c
index 8578cb0d12..f23f098f19 100644
--- a/userdiff.c
+++ b/userdiff.c
@@ -168,6 +168,13 @@ PATTERNS("java",
 	 "|[-+0-9.e]+[fFlL]?|0[xXbB]?[0-9a-fA-F]+[lL]?"
 	 "|[-+*/<>%&^|=!]="
 	 "|--|\\+\\+|<<=?|>>>?=?|&&|\\|\\|"),
+PATTERNS("kotlin",
+	 "^[ \t]*(([a-z]+[ \t]+)*(fun|class|interface)[ \t]+.*[ \t]*)$",
+	 /* -- */
+	 "[a-zA-Z_][a-zA-Z0-9_]*"
+	 "|[-+0-9.e]+[fFlL]?|0[xXbB]?[0-9a-fA-F]+[lL]?"
+	 "|[-+*/<>%&^|=!]="
+	 "|--|\\+\\+|<<=?|>>>?=?|&&|\\|\\|"),
 PATTERNS("markdown",
 	 "^ {0,3}#{1,6}[ \t].*",
 	 /* -- */
