diff --git a/sci-libs/lapack/lapack-3.12.1-r2.ebuild b/sci-libs/lapack/lapack-3.12.1-r2.ebuild
new file mode 100644
index 0000000000000..d05a7a91a70f5
--- /dev/null
+++ b/sci-libs/lapack/lapack-3.12.1-r2.ebuild
@@ -0,0 +1,153 @@
+# Copyright 1999-2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+# Some additional tests are run if Python is found
+PYTHON_COMPAT=( python3_{11..14} )
+inherit cmake flag-o-matic fortran-2 python-any-r1
+
+DESCRIPTION="BLAS, CBLAS, LAPACK, LAPACKE reference implementations"
+HOMEPAGE="https://www.netlib.org/lapack/"
+SRC_URI="https://github.com/Reference-LAPACK/lapack/archive/v${PV}.tar.gz -> ${P}.tar.gz"
+
+LICENSE="BSD"
+SLOT="0"
+KEYWORDS="~alpha ~amd64 ~arm ~arm64 ~hppa ~loong ~mips ~ppc ~ppc64 ~riscv ~s390 ~sparc ~x86 ~amd64-linux ~x86-linux ~arm64-macos ~ppc-macos ~x64-macos"
+IUSE="flexiblas lapacke deprecated doc eselect-ldso index64 test"
+REQUIRED_USE="flexiblas? ( deprecated !eselect-ldso )"
+RESTRICT="!test? ( test )"
+
+RDEPEND="
+	!app-eselect/eselect-cblas
+	virtual/fortran
+	eselect-ldso? (
+		>=app-eselect/eselect-blas-0.2
+		>=app-eselect/eselect-lapack-0.2
+	)
+	doc? ( app-doc/blas-docs )
+"
+DEPEND="${RDEPEND}"
+BDEPEND="
+	virtual/pkgconfig
+	test? ( ${PYTHON_DEPS} )
+"
+PDEPEND="
+	flexiblas? (
+		sci-libs/flexiblas[system-blas(-)]
+	)
+"
+
+PATCHES=(
+	"${FILESDIR}"/${PN}-3.12.1-broken-flow.patch
+	"${FILESDIR}"/${PN}-3.12.1-broken-flow-deux.patch
+	"${FILESDIR}"/${PN}-3.12.1-broken-flow-trois.patch
+	"${FILESDIR}"/${PN}-3.12.1-lapack64-pc.patch
+)
+
+pkg_setup() {
+	fortran-2_pkg_setup
+	use test && python-any-r1_pkg_setup
+}
+
+src_prepare() {
+	cmake_src_prepare
+
+	if use flexiblas; then
+		# install libraries renamed to '*-reference'
+		sed -i -e '/set([A-Z]*LIB/s:"):-reference"):' CMakeLists.txt || die
+	fi
+}
+
+src_configure() {
+	# bug #878891
+	filter-lto
+
+	local mycmakeargs=(
+		-DCBLAS=ON
+		-DLAPACKE=$(usex lapacke)
+		-DBUILD_DEPRECATED=$(usex deprecated)
+		-DBUILD_SHARED_LIBS=ON
+		-DBUILD_TESTING=$(usex test)
+		-DLAPACK_TESTING_USE_PYTHON=$(usex test)
+		# Breaks cross
+		-DTEST_FORTRAN_COMPILER=OFF
+	)
+	if use flexiblas; then
+		mycmakeargs+=(
+			-DCMAKE_INSTALL_INCLUDEDIR=include/lapack-reference
+			# Disable the additional ILP64 symbols in LP64 libraries
+			# for now, to save time.  FlexiBLAS cannot use them
+			# at the moment.
+			-DBUILD_INDEX64_EXT_API=OFF
+		)
+	fi
+
+	cmake_src_configure
+
+	if use index64; then
+		mycmakeargs+=(
+			-DBUILD_INDEX64=ON
+		)
+		BUILD_DIR=${BUILD_DIR}-ilp64 cmake_src_configure
+	fi
+}
+
+src_compile() {
+	cmake_src_compile
+	use index64 && BUILD_DIR=${BUILD_DIR}-ilp64 cmake_src_compile
+}
+
+src_install() {
+	cmake_src_install
+	use index64 && BUILD_DIR=${BUILD_DIR}-ilp64 cmake_src_install
+
+	use eselect-ldso || return
+	# Create private lib directory for eselect::blas (ld.so.conf)
+	dodir /usr/$(get_libdir)/blas/reference
+	dosym -r /usr/$(get_libdir)/libblas.so /usr/$(get_libdir)/blas/reference/libblas.so
+	dosym -r /usr/$(get_libdir)/libblas.so.3 /usr/$(get_libdir)/blas/reference/libblas.so.3
+	dosym -r /usr/$(get_libdir)/libcblas.so /usr/$(get_libdir)/blas/reference/libcblas.so
+	dosym -r /usr/$(get_libdir)/libcblas.so.3 /usr/$(get_libdir)/blas/reference/libcblas.so.3
+
+	# Create private lib directory for eselect::lapack (ld.so.conf)
+	dodir /usr/$(get_libdir)/lapack/reference
+	dosym -r /usr/$(get_libdir)/liblapack.so /usr/$(get_libdir)/lapack/reference/liblapack.so
+	dosym -r /usr/$(get_libdir)/liblapack.so.3 /usr/$(get_libdir)/lapack/reference/liblapack.so.3
+}
+
+pkg_postinst() {
+	use eselect-ldso || return
+
+	local me=reference libdir=$(get_libdir)
+	# check eselect-blas
+	eselect blas add ${libdir} "${EPREFIX}"/usr/${libdir}/blas/${me} ${me}
+	local current_blas=$(eselect blas show ${libdir} | cut -d' ' -f2)
+	if [[ ${current_blas} == ${me} || -z ${current_blas} ]]; then
+		eselect blas set ${libdir} ${me}
+		elog "Current eselect: BLAS ($libdir) -> [${current_blas}]."
+	else
+		elog "Current eselect: BLAS ($libdir) -> [${current_blas}]."
+		elog "To use blas [${me}] implementation, you have to issue (as root):"
+		elog "\t eselect blas set ${libdir} ${me}"
+	fi
+
+	# check eselect-lapack
+	eselect lapack add ${libdir} "${EPREFIX}"/usr/${libdir}/lapack/${me} ${me}
+	local current_lapack=$(eselect lapack show ${libdir} | cut -d' ' -f2)
+	if [[ ${current_lapack} == ${me} || -z ${current_lapack} ]]; then
+		eselect lapack set ${libdir} ${me}
+		elog "Current eselect: LAPACK ($libdir) -> [${current_lapack}]."
+	else
+		elog "Current eselect: LAPACK ($libdir) -> [${current_lapack}]."
+		elog "To use lapack [${me}] implementation, you have to issue (as root):"
+		elog "\t eselect lapack set ${libdir} ${me}"
+	fi
+}
+
+pkg_postrm() {
+	use eselect-ldso || return
+
+	eselect blas validate
+	eselect lapack validate
+}
diff --git a/sci-libs/lapack/metadata.xml b/sci-libs/lapack/metadata.xml
index 539164e91398b..99e27523a2dff 100644
--- a/sci-libs/lapack/metadata.xml
+++ b/sci-libs/lapack/metadata.xml
@@ -28,6 +28,9 @@ This package installs the reference FORTRAN 77 implementation from Netlib.
 	</longdescription>
 	<use>
 		<flag name="deprecated">Also build deprecated functions</flag>
+		<flag name="flexiblas">
+			Rename install files, for system FlexiBLAS compatibility
+		</flag>
 		<flag name="index64">Build a separate ILP64 library in addition to LP64</flag>
 		<flag name="lapacke">Build LAPACKE</flag>
 		<flag name="eselect-ldso">Enable runtime library switching by