diff --git a/sdk_container/src/third_party/coreos-overlay/sys-process/tini/Manifest b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/Manifest
index 57af54f01a..3f87125140 100644
--- a/sdk_container/src/third_party/coreos-overlay/sys-process/tini/Manifest
+++ b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/Manifest
@@ -1,3 +1 @@
 DIST tini-0.19.0.tar.gz 32369 BLAKE2B 5d86f6299b92152063974e6ecd347e1a2ba90f0188f2a702ddb6c814fc1c9723062481fe560caa89e9f74883017ee833566adf1eb1f11fe625671eced47f3296 SHA512 1fa85b56e2c6085ea474f251928e7a40510d92aeef60b3c145b0496969c1b5df86835d143cb91ef5b4bf4da63fa8a56947cc39a4276e4b72faa57276d432b292
-EBUILD tini-0.19.0-r1.ebuild 1628 BLAKE2B bc6b59ecfd8a47645666d1a5ec5c81c983862bf1de483db88e025fd999821d6756ae871519c26f7492d983b3969681efab2f24e73e9cc60a5ef90ab9302e65c1 SHA512 9c414f7de0bbf666a9880bdec0b402dc036d25e52d4ea9c45bcafed3d0e92911cdd50735d244089cd4d61b3e3c29a50a0fb814dd81fa529322933ec2d6bc4346
-MISC metadata.xml 558 BLAKE2B 7fd719d731c968125776805299e964567907ca7cae8a94c717218fdf8caa73d6f333a8bb22c36e0bec273f48504a55f91081e09474abc90440b50bcd760f53aa SHA512 dfbadc5994b3c7b4d8a27fd207c9f1836a21633218dee0252f938448f3c14f3c41d1f35c0604aecbc9f14117b27cd995451800c61dd41875be3becffb53d33f3
diff --git a/sdk_container/src/third_party/coreos-overlay/sys-process/tini/README.md b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/README.md
new file mode 100644
index 0000000000..b7ea2dcbde
--- /dev/null
+++ b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/README.md
@@ -0,0 +1,5 @@
+This is a fork of gentoo's sys-process/tini package. The sole reason
+that this package is in coreos-overlay and not in portage-stable is to
+get rid of the build dependency on cmake, which we do not provide. The
+build system is replaced with a small autotools setup (see
+[files/automake](files/automake)).
diff --git a/sdk_container/src/third_party/coreos-overlay/sys-process/tini/files/automake/Makefile.am b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/files/automake/Makefile.am
new file mode 100644
index 0000000000..af437a64d6
--- /dev/null
+++ b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/files/automake/Makefile.am
@@ -0,0 +1 @@
+SUBDIRS = src
diff --git a/sdk_container/src/third_party/coreos-overlay/sys-process/tini/files/automake/configure.ac b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/files/automake/configure.ac
new file mode 100644
index 0000000000..b4d32b3278
--- /dev/null
+++ b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/files/automake/configure.ac
@@ -0,0 +1,12 @@
+AC_INIT([tini], [0.1])
+AC_PROG_CC
+
+AM_INIT_AUTOMAKE([])
+
+AC_SUBST(tini_VERSION_MAJOR)
+AC_SUBST(tini_VERSION_MINOR)
+AC_SUBST(tini_VERSION_PATCH)
+AC_SUBST(tini_VERSION_GIT)
+
+AC_CONFIG_FILES([Makefile src/Makefile src/tiniConfig.h tpl/VERSION])
+AC_OUTPUT
diff --git a/sdk_container/src/third_party/coreos-overlay/sys-process/tini/files/automake/src/Makefile.am b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/files/automake/src/Makefile.am
new file mode 100644
index 0000000000..115d247d5d
--- /dev/null
+++ b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/files/automake/src/Makefile.am
@@ -0,0 +1,4 @@
+bin_PROGRAMS = tini
+tini_SOURCES = tini.c
+
+tini_CFLAGS = -static
diff --git a/sdk_container/src/third_party/coreos-overlay/sys-process/tini/tini-0.19.0-r1.ebuild b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/tini-0.19.0-r1.ebuild
index fe80f91738..a1279af126 100644
--- a/sdk_container/src/third_party/coreos-overlay/sys-process/tini/tini-0.19.0-r1.ebuild
+++ b/sdk_container/src/third_party/coreos-overlay/sys-process/tini/tini-0.19.0-r1.ebuild
@@ -1,66 +1,42 @@
-# Copyright 1999-2021 Gentoo Authors
+# Copyright 1999-2020 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
+# Flatcar: Based on tini-0.18.0.ebuild from commit
+# d6c89a5caedbe5cae98142ebb99974b41177aedd in gentoo repo (see
+# https://gitweb.gentoo.org/repo/gentoo.git/plain/sys-process/tini/tini-0.18.0.ebuild?id=d6c89a5caedbe5cae98142ebb99974b41177aedd).
+
 EAPI=7
 
-inherit cmake flag-o-matic
-
-# guard against forgetfulness, https://bugs.gentoo.org/795936
-GIT_COMMIT_0190="de40ad007797e0dcd8b7126f27bb87401d224240"
-GIT_COMMIT="GIT_COMMIT_${PV//./}"
-GIT_COMMIT="${!GIT_COMMIT}"
+# Flatcar: We provide our autotools-based build system to avoid build
+# dependency on cmake. So the settings are hardcoded in the build
+# system - we want static binary and a non-minimal build.
+inherit autotools
 
+GIT_COMMIT=de40ad007797e0dcd8b7126f27bb87401d224240
 DESCRIPTION="A tiny but valid init for containers"
 HOMEPAGE="https://github.com/krallin/tini"
 SRC_URI="https://github.com/krallin/${PN}/archive/v${PV}.tar.gz -> ${P}.tar.gz"
 
 LICENSE="MIT"
 SLOT="0"
-KEYWORDS="amd64 ~arm arm64 ppc64 ~x86"
-IUSE="+args +static"
+# Flatcar: We don't mark arm64 as "testing".
+KEYWORDS="amd64 arm64"
+# Flatcar: No IUSE on args or on static - it's hardcoded in the build
+# system replacement.
 
 src_prepare() {
+	# Flatcar: We don't use cmake, so all the code handling cmake
+	# stuff is dropped. Autotools provide the standard configure
+	# && make && make install build protocol, which Gentoo handles
+	# out of the box.
+	for file in configure.ac Makefile.am src/Makefile.am; do
+		cp "${FILESDIR}/automake/${file}" "${S}/${file}"
+	done
+	eapply_user
 
-	[[ -z ${GIT_COMMIT} ]] && die "forgetful maintainer! please define GIT_COMMIT_${PV//./} on bump"
-
-	cmake_src_prepare
-
-	local sed_args=(
-		# Do not strip binary
-		-e 's/-Wl,-s")$/")/'
-
-		# Remove -Werror and -pedantic-errors in order to allow macro
-		# redefinition, so that CFLAGS="-U_FORTIFY_SOURCE" does not
-		# trigger an error due to add_definitions(-D_FORTIFY_SOURCE=2)
-		# in CMakeLists.txt (bug 626438).
-		-e "s/ -Werror / /"
-		-e "s/ -pedantic-errors / /"
-	)
-
-	sed -i "${sed_args[@]}" \
-		-e "s/git.*status --porcelain.*/true/" \
-		-e "s/git.*log -n 1.*/true/" \
-		-e "s/git.\${tini_VERSION_GIT}/git.${GIT_COMMIT}/" \
-		CMakeLists.txt || die
-}
-
-src_configure() {
-	local mycmakeargs=()
-	use args || mycmakeargs+=(-DMINIMAL=ON)
-
-	cmake_src_configure
-}
-
-src_compile() {
-	append-cflags -DPR_SET_CHILD_SUBREAPER=36 -DPR_GET_CHILD_SUBREAPER=37
-	cmake_src_compile
-}
-
-src_install() {
-	cmake_src_install
-	if use static; then
-		mv "${ED}"/usr/bin/{${PN}-static,${PN}} || die
-	else
-		rm "${ED}"/usr/bin/${PN}-static || die
-	fi
+	export tini_VERSION_MAJOR=$(ver_cut 1)
+	export tini_VERSION_MINOR=$(ver_cut 2)
+	export tini_VERSION_PATCH=$(ver_cut 3)
+	export tini_VERSION_GIT=${GIT_COMMIT}
+	eautoreconf
 }