diff --git a/sci-libs/flexiblas/flexiblas-3.4.82-r4.ebuild b/sci-libs/flexiblas/flexiblas-3.4.82-r4.ebuild
new file mode 100644
index 0000000000000..51b77796acdcf
--- /dev/null
+++ b/sci-libs/flexiblas/flexiblas-3.4.82-r4.ebuild
@@ -0,0 +1,281 @@
+# Copyright 2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+inherit cmake multilib toolchain-funcs
+
+MY_P=flexiblas-release-v${PV}
+DESCRIPTION="A BLAS and LAPACK wrapper library with runtime exchangable backends"
+HOMEPAGE="
+	https://www.mpi-magdeburg.mpg.de/projects/flexiblas/
+	https://gitlab.mpi-magdeburg.mpg.de/software/flexiblas-release/
+"
+SRC_URI="
+	https://gitlab.mpi-magdeburg.mpg.de/software/flexiblas-release/-/archive/v${PV}/${MY_P}.tar.bz2
+"
+S=${WORKDIR}/${MY_P}
+
+# BSD for vendored cblas/lapacke
+LICENSE="LGPL-3+ BSD"
+SLOT="0"
+KEYWORDS="~amd64 ~arm ~arm64 ~ppc ~ppc64 ~riscv ~x86"
+IUSE="blis index64 mkl openblas openmp system-blas tbb test"
+RESTRICT="!test? ( test )"
+
+# flexiblas only supports gnu-openmp using clang/gcc
+DEPEND="
+	sci-libs/lapack:=[deprecated,index64(-)?]
+	blis? ( sci-libs/blis:=[-64bit-index(-),index64(-)?] )
+	mkl? (
+		sci-libs/mkl:=[tbb?]
+		openmp? ( sci-libs/mkl[gnu-openmp] )
+	)
+	openblas? ( sci-libs/openblas:=[index64(-)?] )
+	system-blas? ( sci-libs/lapack[flexiblas(-)] )
+"
+RDEPEND="
+	${DEPEND}
+	system-blas? (
+		!app-eselect/eselect-blas
+		!app-eselect/eselect-cblas
+		!app-eselect/eselect-lapack
+		!sci-libs/lapack[-flexiblas(-)]
+		!=sci-libs/blas-lapack-aux-wrapper-0-r0
+	)
+"
+PDEPEND="
+	system-blas? (
+		>=sci-libs/blas-lapack-aux-wrapper-0-r1[index64?]
+	)
+"
+
+pkg_pretend() {
+	if [[ ${MERGE_TYPE} != binary ]] && use openmp; then
+		tc-check-openmp
+	fi
+}
+
+pkg_setup() {
+	if [[ ${MERGE_TYPE} != binary ]] && use openmp; then
+		tc-check-openmp
+	fi
+}
+
+src_prepare() {
+	local PATCHES=(
+		# extracted from
+		# https://gitlab.mpi-magdeburg.mpg.de/software/flexiblas-release/-/commit/04021ceada30f136036a22dc6c811b3d352b199d
+		"${FILESDIR}/${P}-xerbla-array.patch"
+	)
+
+	cmake_src_prepare
+
+	# remove bundled netlib blas/lapack
+	# (we still need vendored cblas/lapacke)
+	rm -r contributed/lapack-* || die
+}
+
+src_configure() {
+	BACKENDS=( $(usev blis) $(usev openblas) )
+	local extra=${BACKENDS[*]}
+	local libdir="${ESYSROOT}/usr/$(get_libdir)"
+	local mycmakeargs=(
+		-DTESTS=$(usex test)
+		-DCBLAS=ON
+		-DINTEGER8=OFF
+		-DLAPACK=ON
+		-DLINK_OPENMP=$(usex openmp)
+		-DEXAMPLES=OFF
+		# prefer OpenBLAS if available
+		-DFLEXIBLAS_DEFAULT=$(usex openblas openblas netlib)
+		# we need to enable autodetection for mkl
+		-DBLAS_AUTO_DETECT=ON
+		# ...so we need to explicitly disable autodetecting other libraries
+		# that would be pinned to their openmp/pthread/serial variants
+		-DOpenBLASSerial=OFF
+		-DOpenBLASPThread=OFF
+		-DOpenBLASOpenMP=OFF
+		-DOpenBLASSerial64=OFF
+		-DOpenBLASPThread64=OFF
+		-DOpenBLASOpenMP64=OFF
+		-DBlisSerial=OFF
+		-DBlisPThread=OFF
+		-DBlisOpenMP=OFF
+		-DBlisSerial64=OFF
+		-DBlisPThread64=OFF
+		-DBlisOpenMP64=OFF
+		# variants we use autodetection for
+		-DMklSerial=$(usex mkl ON OFF)
+		-DMklOpenMP=$(usex mkl "$(usex openmp ON OFF)" OFF)
+		-DMklTBB=$(usex mkl "$(usex tbb ON OFF)" OFF)
+		# unsupported
+		-DCMAKE_DISABLE_FIND_PACKAGE_nvpl=ON
+		-DATLAS=OFF
+		-DTATLAS=OFF
+		# and then enable our custom names via EXTRA
+		-DEXTRA="${extra// /;}"
+		# respect CFLAGS
+		-DLTO=OFF
+		# these are used only with -DEXTRA
+		-Dblis_LIBRARY="${libdir}/libblis.so"
+		-Dopenblas_LIBRARY="${libdir}/libopenblas.so"
+	)
+
+	# use system sci-libs/lapack
+	if use system-blas; then
+		# this is sci-libs/lapack[flexiblas] install
+		mycmakeargs+=(
+			-DSYS_BLAS_LIBRARY="${libdir}/libblas-reference.so"
+			-DSYS_LAPACK_LIBRARY="${libdir}/liblapack-reference.so"
+		)
+	else
+		mycmakeargs+=(
+			-DSYS_BLAS_LIBRARY="${libdir}/libblas.so"
+			-DSYS_LAPACK_LIBRARY="${libdir}/liblapack.so"
+		)
+	fi
+
+	cmake_src_configure
+
+	if use index64; then
+		mycmakeargs+=(
+			-DINTEGER8=ON
+			-Dblis_LIBRARY="${libdir}/libblis64.so"
+			-Dopenblas_LIBRARY="${libdir}/libopenblas64.so"
+		)
+
+		if use system-blas; then
+			# this is sci-libs/lapack[flexiblas] install
+			mycmakeargs+=(
+				-DSYS_BLAS_LIBRARY="${libdir}/libblas64-reference.so"
+				-DSYS_LAPACK_LIBRARY="${libdir}/liblapack64-reference.so"
+			)
+		else
+			mycmakeargs+=(
+				-DSYS_BLAS_LIBRARY="${libdir}/libblas64.so"
+				-DSYS_LAPACK_LIBRARY="${libdir}/liblapack64.so"
+			)
+		fi
+
+		BUILD_DIR=${BUILD_DIR}-ilp64 cmake_src_configure
+	fi
+
+	BACKENDS+=( netlib )
+	BACKENDS_ILP64=( "${BACKENDS[@]}" )
+	if use mkl; then
+		BACKENDS+=(
+			MklSerial
+			$(usev openmp MklOpenMP)
+			$(usev tbb MklTBB)
+		)
+		BACKENDS_ILP64+=(
+			MklSerial64
+			$(usev openmp MklOpenMP64)
+			$(usev tbb MklTBB64)
+		)
+	fi
+}
+
+src_compile() {
+	cmake_src_compile
+	use index64 && BUILD_DIR=${BUILD_DIR}-ilp64 cmake_src_compile
+}
+
+my_test() {
+	# We run tests in parallel, so avoid having n^2 threads.
+	local -x BLIS_NUM_THREADS=1
+	local -x MKL_NUM_THREADS=1
+	local -x OMP_NUM_THREADS=1
+	local -x OPENBLAS_NUM_THREADS=1
+
+	local failures=()
+	local backend
+	for backend in "${@}"; do
+		# TODO: remove this, and XFAIL them properly when cmake.eclass
+		# is fixed to respect nonfatal, https://bugs.gentoo.org/961929
+		if [[ ${backend} == Mkl* ]]; then
+			einfo "Skipping ${backend} tests, XFAIL"
+			continue
+		fi
+
+		local -x FLEXIBLAS_TEST=${backend}
+		local log=${BUILD_DIR}/Testing/Temporary/LastTest.log
+		einfo "Testing backend ${backend}"
+		if ! nonfatal cmake_src_test; then
+			failures+=( "${backend}" )
+		fi
+		if grep -q 'BLAS backend .* not found' "${log}"; then
+			die "Backend ${backend} failed to load while testing, see ${log}"
+		fi
+	done
+
+	if [[ ${failures[@]} ]]; then
+		die "Test runs failed for backends: ${failures[*]}"
+	fi
+}
+
+src_test() {
+	my_test "${BACKENDS[@]}"
+	use index64 && BUILD_DIR=${BUILD_DIR}-ilp64 my_test "${BACKENDS_ILP64[@]}"
+}
+
+verify_backends() {
+	local lib=${1}
+	shift
+	cd "${ED}/usr/$(get_libdir)/${lib}" || die
+
+	local missing=()
+	local backend
+	for backend in "${@}"; do
+		if [[ ! -f libflexiblas_${backend,,}$(get_libname) ]]; then
+			missing+=( "${backend}" )
+		fi
+	done
+
+	if [[ ${missing[@]} ]]; then
+		die "Not all requested ${lib} backends built. Missing: ${missing[*]}"
+	fi
+}
+
+src_install() {
+	cmake_src_install
+	use index64 && BUILD_DIR=${BUILD_DIR}-ilp64 cmake_src_install
+
+	# Verify built backends.
+	verify_backends flexiblas "${BACKENDS[@]}"
+	use index64 && verify_backends flexiblas64 "${BACKENDS_ILP64[@]}"
+
+	# Install symlinks for system BLAS / LAPACK use.
+	if use system-blas; then
+		local libdir="/usr/$(get_libdir)"
+		local fn suffix
+		for fn in cblas.h lapack.h lapacke{,_config,_mangling,_utils}.h; do
+			dosym "flexiblas/${fn}" "/usr/include/${fn}"
+		done
+
+		for suffix in '' $(usev index64 64); do
+			for fn in blas cblas lapack lapacke; do
+				dosym "libflexiblas${suffix}.so.3" \
+					"${libdir}/lib${fn}${suffix}.so.3"
+			done
+		done
+	fi
+}
+
+pkg_postinst() {
+	if use system-blas; then
+		# eselect-{blas,lapack} doesn't clean up its configs
+		local prev_opt=$(shopt -p nullglob)
+		shopt -s nullglob
+		local files=(
+			"${EROOT}"/etc/ld.so.conf.d/81-blas-*.conf
+			"${EROOT}"/etc/ld.so.conf.d/82-lapack-*.conf
+		)
+		${prev_opt}
+
+		if [[ ${files[@]} ]]; then
+			rm -v "${files[@]}"
+		fi
+	fi
+}
diff --git a/sci-libs/flexiblas/flexiblas-9999.ebuild b/sci-libs/flexiblas/flexiblas-9999.ebuild
index 13f3775404c0f..9aff3ceea4398 100644
--- a/sci-libs/flexiblas/flexiblas-9999.ebuild
+++ b/sci-libs/flexiblas/flexiblas-9999.ebuild
@@ -17,7 +17,7 @@ EGIT_REPO_URI="
 # BSD for vendored cblas/lapacke
 LICENSE="LGPL-3+ BSD"
 SLOT="0"
-IUSE="blis elibc_glibc index64 mkl openblas openmp system-blas tbb test"
+IUSE="blis index64 mkl openblas openmp system-blas tbb test"
 RESTRICT="!test? ( test )"
 
 # flexiblas only supports gnu-openmp using clang/gcc
@@ -38,13 +38,12 @@ RDEPEND="
 		!app-eselect/eselect-cblas
 		!app-eselect/eselect-lapack
 		!sci-libs/lapack[-flexiblas(-)]
+		!=sci-libs/blas-lapack-aux-wrapper-0-r0
 	)
 "
 PDEPEND="
 	system-blas? (
-		elibc_glibc? (
-			sci-libs/blas-lapack-aux-wrapper[index64?]
-		)
+		>=sci-libs/blas-lapack-aux-wrapper-0-r1[index64?]
 	)
 "
 
@@ -246,19 +245,12 @@ src_install() {
 			dosym "flexiblas/${fn}" "/usr/include/${fn}"
 		done
 
-		# On glibc, we can use sci-libs/blas-lapack-aux-wrapper.
-		if ! use elibc_glibc; then
-			for suffix in '' $(usev index64 64); do
-				for fn in blas cblas lapack lapacke; do
-					dosym "libflexiblas${suffix}.so.3" \
-						"${libdir}/lib${fn}${suffix}.so.3"
-					dosym "libflexiblas${suffix}.so" \
-						"${libdir}/lib${fn}${suffix}.so"
-					dosym "flexiblas${suffix}.pc" \
-						"${libdir}/pkgconfig/${fn}${suffix}.pc"
-				done
+		for suffix in '' $(usev index64 64); do
+			for fn in blas cblas lapack lapacke; do
+				dosym "libflexiblas${suffix}.so.3" \
+					"${libdir}/lib${fn}${suffix}.so.3"
 			done
-		fi
+		done
 	fi
 }