diff --git a/.bumpversion.cfg b/.bumpversion.cfg
index df6ef20..9ad2742 100644
--- a/.bumpversion.cfg
+++ b/.bumpversion.cfg
@@ -1,7 +1,7 @@
 [bumpversion]
 commit = True
 tag = True
-current_version = 3.27
+current_version = 4.0
 parse = (?P<major>\d+)\.(?P<minor>\d+)
 serialize = 
 	{major}.{minor}
diff --git a/man/ustreamer-dump.1 b/man/ustreamer-dump.1
index 55c48c4..5297ae7 100644
--- a/man/ustreamer-dump.1
+++ b/man/ustreamer-dump.1
@@ -1,6 +1,6 @@
 .\" Manpage for ustreamer-dump.
 .\" Open an issue or pull request to https://github.com/pikvm/ustreamer to correct errors or typos
-.TH USTREAMER-DUMP 1 "version 3.27" "January 2021"
+.TH USTREAMER-DUMP 1 "version 4.0" "January 2021"
 
 .SH NAME
 ustreamer-dump \- Dump uStreamer's memory sink to file
diff --git a/man/ustreamer.1 b/man/ustreamer.1
index 86028d1..3acaa88 100644
--- a/man/ustreamer.1
+++ b/man/ustreamer.1
@@ -1,6 +1,6 @@
 .\" Manpage for ustreamer.
 .\" Open an issue or pull request to https://github.com/pikvm/ustreamer to correct errors or typos
-.TH USTREAMER 1 "version 3.27" "November 2020"
+.TH USTREAMER 1 "version 4.0" "November 2020"
 
 .SH NAME
 ustreamer \- stream MJPG video from any V4L2 device to the network
diff --git a/pkg/arch/PKGBUILD b/pkg/arch/PKGBUILD
index 9d40cdd..04c641d 100644
--- a/pkg/arch/PKGBUILD
+++ b/pkg/arch/PKGBUILD
@@ -3,7 +3,7 @@
 
 
 pkgname=ustreamer
-pkgver=3.27
+pkgver=4.0
 pkgrel=1
 pkgdesc="Lightweight and fast MJPG-HTTP streamer"
 url="https://github.com/pikvm/ustreamer"
diff --git a/pkg/openwrt/Makefile b/pkg/openwrt/Makefile
index f119fae..3323d7f 100644
--- a/pkg/openwrt/Makefile
+++ b/pkg/openwrt/Makefile
@@ -6,7 +6,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=ustreamer
-PKG_VERSION:=3.27
+PKG_VERSION:=4.0
 PKG_RELEASE:=1
 PKG_MAINTAINER:=Maxim Devaev <mdevaev@gmail.com>
 
diff --git a/python/setup.py b/python/setup.py
index 56e546a..afa233a 100644
--- a/python/setup.py
+++ b/python/setup.py
@@ -8,7 +8,7 @@ from distutils.core import setup
 if __name__ == "__main__":
     setup(
         name="ustreamer",
-        version="3.27",
+        version="4.0",
         description="uStreamer tools",
         author="Maxim Devaev",
         author_email="mdevaev@gmail.com",
diff --git a/src/libs/config.h b/src/libs/config.h
index 9c2bc55..7c9d749 100644
--- a/src/libs/config.h
+++ b/src/libs/config.h
@@ -22,8 +22,8 @@
 
 #pragma once
 
-#define VERSION_MAJOR 3
-#define VERSION_MINOR 27
+#define VERSION_MAJOR 4
+#define VERSION_MINOR 0
 
 #define MAKE_VERSION2(_major, _minor) #_major "." #_minor
 #define MAKE_VERSION1(_major, _minor) MAKE_VERSION2(_major, _minor)