diff --git a/dev-libs/libbytesize/Manifest b/dev-libs/libbytesize/Manifest
index 05d9ee51853b8..c9e20a5ada7ef 100644
--- a/dev-libs/libbytesize/Manifest
+++ b/dev-libs/libbytesize/Manifest
@@ -1 +1,2 @@
 DIST libbytesize-2.11.tar.gz 459631 BLAKE2B f15b260f3abfdd876a45157281e7a3dbc33227ef0fa8096a07b254b5edf7378af0653b43b54d0d1ac780ad900644039bd73a0bc9a5c6a111fb45d69e4065cbdc SHA512 eb539c878cc0f857772b07aac4aca2732d3298fa649011f3f8a95fce83b1cc5b5b7001f6bb0c168ed47b7886d34c2e139ded9e66994a9a10784f9f7944475190
+DIST libbytesize-2.12.tar.gz 472481 BLAKE2B 3bc52c4752d54f82005dc6a7ad7f5044a26cf4d71643767149160ee5ffa2a486ac39f2d2fa15097fd6ecb4c242231adf3e39d76bd3f10eb8240cdc96680f9211 SHA512 90eaa77b9e2cdafa1ac9e286c11fd7304c00146d0c33e942e36636968933cc683c00de7a3f715123b302fd9b2013ac4620c52371be7c69a1b33e02570847b091
diff --git a/dev-libs/libbytesize/libbytesize-2.12.ebuild b/dev-libs/libbytesize/libbytesize-2.12.ebuild
new file mode 100644
index 0000000000000..62a7ee0e24844
--- /dev/null
+++ b/dev-libs/libbytesize/libbytesize-2.12.ebuild
@@ -0,0 +1,88 @@
+# Copyright 1999-2026 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{10..13} )
+
+inherit autotools python-r1
+
+DESCRIPTION="Tiny library providing a C \"class\" for working with arbitrary big byte sizes"
+HOMEPAGE="https://github.com/storaged-project/libbytesize"
+SRC_URI="https://github.com/storaged-project/libbytesize/releases/download/${PV}/${P}.tar.gz"
+
+LICENSE="LGPL-2+"
+SLOT="0"
+KEYWORDS="~alpha ~amd64 ~arm ~arm64 ~loong ~mips ~ppc ~ppc64 ~riscv ~sparc ~x86"
+IUSE="doc python test tools"
+RESTRICT="!test? ( test )"
+
+REQUIRED_USE="
+	python? ( ${PYTHON_REQUIRED_USE} )
+	tools? ( python )
+"
+
+RDEPEND="
+	dev-libs/gmp:=
+	dev-libs/mpfr:=
+	dev-libs/libpcre2:=
+	python? ( ${PYTHON_DEPS} )
+"
+DEPEND="${RDEPEND}"
+BDEPEND="
+	sys-devel/gettext
+	doc? (
+		dev-util/gtk-doc
+		virtual/pkgconfig
+	)
+	test? (
+		dev-python/pocketlint[${PYTHON_USEDEP}]
+		dev-python/polib[${PYTHON_USEDEP}]
+	)
+"
+
+PATCHES=(
+	"${FILESDIR}/${PN}-2.4-no_Werror.patch"
+)
+
+python_do() {
+	if use python ; then
+		python_foreach_impl run_in_build_dir "$@"
+	else
+		"$@"
+	fi
+}
+
+src_prepare() {
+	default
+	eautoreconf
+}
+
+src_configure() {
+	local myeconfargs=(
+		$(use_with doc gtk-doc)
+		$(use_with python python3)
+		$(use_with tools)
+	)
+	local ECONF_SOURCE="${S}"
+	python_do econf "${myeconfargs[@]}"
+}
+
+src_compile() {
+	python_do emake
+}
+
+src_test() {
+	python_do emake check
+}
+
+install_helper() {
+	emake DESTDIR="${D}" install
+	use python && python_optimize
+}
+
+src_install() {
+	python_do install_helper
+	einstalldocs
+	find "${ED}" -name "*.la" -type f -delete || die
+}