diff --git a/app-misc/tmux/tmux-2.5-r1.ebuild b/app-misc/tmux/tmux-2.5-r1.ebuild
new file mode 100644
index 0000000000000..41a775981641d
--- /dev/null
+++ b/app-misc/tmux/tmux-2.5-r1.ebuild
@@ -0,0 +1,91 @@
+# Copyright 1999-2017 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=6
+
+inherit autotools flag-o-matic versionator
+
+DESCRIPTION="Terminal multiplexer"
+HOMEPAGE="http://tmux.github.io/"
+SRC_URI="https://github.com/${PN}/${PN}/releases/download/${PV/_*}/${P/_/-}.tar.gz"
+
+LICENSE="ISC"
+SLOT="0"
+KEYWORDS="~alpha ~amd64 ~arm ~arm64 ~hppa ~ia64 ~mips ~ppc ~ppc64 ~s390 ~sh ~sparc ~x86 ~amd64-fbsd ~x86-fbsd ~amd64-linux ~x86-linux ~ppc-macos ~x64-macos ~x86-macos"
+IUSE="debug selinux utempter vim-syntax kernel_FreeBSD kernel_linux"
+
+CDEPEND="
+	dev-libs/libevent:0=
+	sys-libs/ncurses:0=
+	utempter? (
+		kernel_linux? ( sys-libs/libutempter )
+		kernel_FreeBSD? ( || ( >=sys-freebsd/freebsd-lib-9.0 sys-libs/libutempter ) )
+	)"
+
+DEPEND="
+	${CDEPEND}
+	virtual/pkgconfig"
+
+RDEPEND="
+	${CDEPEND}
+	selinux? ( sec-policy/selinux-screen )
+	vim-syntax? (
+		|| (
+			app-editors/vim
+			app-editors/gvim
+		)
+	)"
+
+DOCS=( CHANGES FAQ README TODO example_tmux.conf )
+
+PATCHES=(
+	# usptream fixes (can be removed with next version bump)
+	"${FILESDIR}/${PN}-2.4-flags.patch"
+)
+
+S="${WORKDIR}/${P/_/-}"
+
+src_prepare() {
+	# bug 438558
+	# 1.7 segfaults when entering copy mode if compiled with -Os
+	replace-flags -Os -O2
+
+	# regenerate aclocal.m4 to support earlier automake versions
+	rm -v aclocal.m4 || die
+
+	default
+	eautoreconf
+}
+
+src_configure() {
+	local myeconfargs=(
+		--sysconfdir="${EPREFIX}"/etc
+		$(use_enable debug)
+		$(use_enable utempter)
+	)
+
+	econf "${myeconfargs[@]}"
+}
+
+src_install() {
+	default
+
+	if use vim-syntax; then
+		insinto /usr/share/vim/vimfiles/ftdetect
+		doins "${FILESDIR}"/tmux.vim
+	fi
+}
+
+pkg_postinst() {
+	if ! version_is_at_least 1.9a ${REPLACING_VERSIONS:-1.9a}; then
+		echo
+		ewarn "Some configuration options changed in this release."
+		ewarn "Please read the CHANGES file in /usr/share/doc/${PF}/"
+		ewarn
+		ewarn "WARNING: After updating to ${P} you will _not_ be able to connect to any"
+		ewarn "older, running tmux server instances. You'll have to use an existing client to"
+		ewarn "end your old sessions or kill the old server instances. Otherwise you'll have"
+		ewarn "to temporarily downgrade to access them."
+		echo
+	fi
+}