diff --git a/app-editors/xemacs/files/xemacs-21.5.36-cus-dep.patch b/app-editors/xemacs/files/xemacs-21.5.36-cus-dep.patch
new file mode 100644
index 0000000000000..e909fffa370e1
--- /dev/null
+++ b/app-editors/xemacs/files/xemacs-21.5.36-cus-dep.patch
@@ -0,0 +1,27 @@
+changeset:   7825:d1d026a0f073
+tag:         tip
+user:        Aidan Kehoe <kehoea@parhasard.net>
+date:        Wed Nov 26 07:16:47 2025 +0000
+summary:     Avoid generating a lock file when generating custom-load.el, cus-dep.el
+
+diff -r c562b019a23b -r d1d026a0f073 lisp/cus-dep.el
+--- a/lisp/cus-dep.el	Tue Nov 25 13:38:30 2025 +0000
++++ b/lisp/cus-dep.el	Wed Nov 26 07:16:47 2025 +0000
+@@ -119,12 +119,11 @@
+ 		       (return nil))))
+ 	      (message "(No changes need to be written)")
+ 	    (when (file-exists-p cusload-file)
+-	      (let ((buf (find-file-noselect cusload-file)))
+-		(with-current-buffer buf
+-		  (goto-char (point-min))
+-		  (when (search-forward cusload-hash-table-marker nil t)
+-		    (setq old-hash (read buf))))
+-		(kill-buffer buf)))
++             (with-temp-buffer
++               (insert-file-contents-internal cusload-file)
++               (goto-char (point-min))
++               (when (search-forward cusload-hash-table-marker nil t)
++                 (setq old-hash (read (current-buffer))))))
+ 	    ;; Process directory
+ 	    (dolist (file files)
+ 	      (let ((old-cache (if (hash-table-p old-hash)
diff --git a/app-editors/xemacs/xemacs-21.5.36-r4.ebuild b/app-editors/xemacs/xemacs-21.5.36-r4.ebuild
new file mode 100644
index 0000000000000..e54e3b01a628c
--- /dev/null
+++ b/app-editors/xemacs/xemacs-21.5.36-r4.ebuild
@@ -0,0 +1,257 @@
+# Copyright 1999-2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+# Note: xemacs currently does not work with position independent code
+# so the build forces the use of the -no-pie option
+
+EAPI=8
+
+inherit flag-o-matic xdg-utils desktop autotools
+
+DESCRIPTION="highly customizable open source text editor and application development system"
+HOMEPAGE="https://www.xemacs.org/"
+
+SRC_URI="http://ftp.xemacs.org/pub/xemacs/xemacs-$(ver_cut 1-2)/${P}.tar.gz
+	neXt? ( http://www.malfunction.de/afterstep/files/NeXT_XEmacs.tar.gz )"
+
+LICENSE="GPL-3+"
+SLOT="0"
+KEYWORDS="~alpha ~amd64 ~arm64 ~hppa ~ppc ~ppc64 ~riscv ~sparc ~x86"
+IUSE="alsa debug gif gpm pop postgres ldap xface nas X jpeg tiff png motif xft xim athena neXt Xaw3d gdbm berkdb +bignum"
+
+X_DEPEND="x11-libs/libXt x11-libs/libXmu x11-libs/libXext x11-misc/xbitmaps"
+
+# If sys-libs/db:5.3 is removed from tree 4.8 can be used.
+RDEPEND="
+	berkdb? ( sys-libs/db:5.3= )
+	gdbm? ( >=sys-libs/gdbm-1.8.3:=[berkdb(+)] )
+	>=virtual/zlib-1.1.4:=
+	>=dev-libs/openssl-0.9.6:0=
+	>=media-libs/audiofile-0.2.3
+	gpm? ( >=sys-libs/gpm-1.19.6 )
+	postgres? ( dev-db/postgresql:= )
+	ldap? ( net-nds/openldap:= )
+	alsa? ( media-libs/alsa-lib )
+	nas? ( media-libs/nas )
+	X? ( $X_DEPEND !Xaw3d? ( !neXt? ( x11-libs/libXaw ) ) )
+	motif? ( >=x11-libs/motif-2.3:0[xft=] )
+	athena? ( x11-libs/libXaw )
+	Xaw3d? ( x11-libs/libXaw3d[unicode(+)] )
+	xft? ( media-libs/freetype:2 x11-libs/libXft x11-libs/libXrender >=media-libs/fontconfig-2.5.0 )
+	neXt? ( x11-libs/neXtaw )
+	xface? ( media-libs/compface )
+	tiff? ( media-libs/tiff:= )
+	png? ( >=media-libs/libpng-1.2:0 )
+	jpeg? ( media-libs/libjpeg-turbo:= )
+	>=sys-libs/ncurses-5.2:=
+	>=app-eselect/eselect-emacs-1.15
+	bignum? ( dev-libs/openssl )"
+
+DEPEND="${RDEPEND}
+	virtual/pkgconfig"
+
+BDEPEND="sys-apps/texinfo"
+
+PDEPEND="app-xemacs/xemacs-base
+	app-xemacs/mule-base"
+
+src_unpack() {
+	default_src_unpack
+}
+
+src_prepare() {
+	use neXt && cp "${WORKDIR}"/NeXT.XEmacs/xemacs-icons/* "${S}"/etc/toolbar/
+	find "${S}"/lisp -name '*.elc' -exec rm {} \; || die
+	eapply "${FILESDIR}/${PN}-21.5.35-unknown-command-test.patch"
+	eapply "${FILESDIR}/${P}-failing-tests.patch"
+	eapply "${FILESDIR}/${P}-failing-tests-2.patch"
+	eapply "${FILESDIR}/${P}-configure-postgresql.patch"
+	eapply "${FILESDIR}/${P}-berkdb-5.3.patch"
+	eapply "${FILESDIR}/${P}-cus-dep.patch"
+	eapply_user
+
+	eautoconf
+
+	# Some binaries and man pages are installed under suffixed names
+	# to avoid collions with their GNU Emacs counterparts (see below).
+	# Fix internal filename references.
+	sed -i -e 's/exec gnuclient/&-xemacs/' lib-src/gnudoit || die
+	sed -i -e '/^\.so/s/etags/&-xemacs/' etc/ctags.1 || die
+	sed -i -e '/^\.so/s/gnuserv/&-xemacs/' etc/gnu{client,doit,attach}.1 || die
+}
+
+src_configure() {
+	local myconf=""
+
+	# bug #639642
+	test-flags -no-pie >/dev/null && append-flags -no-pie
+	filter-flags -pie
+
+	if use X; then
+
+		myconf="${myconf} --with-widgets=athena"
+		myconf="${myconf} --with-dialogs=athena"
+		myconf="${myconf} --with-menubars=lucid"
+		myconf="${myconf} --with-scrollbars=lucid"
+		if use motif ; then
+			myconf="--with-widgets=motif"
+			myconf="${myconf} --with-dialogs=motif"
+			myconf="${myconf} --with-scrollbars=motif"
+			myconf="${myconf} --with-menubars=lucid"
+		fi
+		if use athena or use Xaw3d ; then
+			myconf="--with-scrollbars=athena"
+		fi
+
+		if use Xaw3d; then
+			myconf="${myconf} --with-athena=3d"
+		elif use neXt; then
+			myconf="${myconf} --with-athena=next"
+		else
+			myconf="${myconf} --with-athena=xaw"
+		fi
+
+		myconf="${myconf} $(use_with tiff )"
+		myconf="${myconf} $(use_with png )"
+		myconf="${myconf} $(use_with jpeg )"
+		myconf="${myconf} $(use_with xface )"
+
+		use xft && myconf="${myconf} --with-xft=emacs,tabs,menubars,gauges" ||
+			myconf="${myconf} --with-xft=no"
+
+	else
+		myconf="${myconf}
+			--without-x
+			--without-xpm
+			--without-dragndrop
+			--with-xft=no
+			--with-gif=no"
+	fi
+
+	if use xim ; then
+		if use motif ; then
+			myconf="${myconf} --with-xim=motif"
+		else
+			myconf="${myconf} --with-xim=xlib"
+		fi
+	else
+		myconf="${myconf} --with-xim=no"
+	fi
+
+	myconf="${myconf} --without-wnn"
+
+	# This determines the type of sounds we are playing
+	local soundconf="native"
+
+	# This determines how these sounds should be played
+	use nas	&& soundconf="${soundconf},nas"
+	use alsa && soundconf="${soundconf},alsa"
+
+	myconf="${myconf} --with-sound=${soundconf}"
+
+	if use gdbm || use berkdb ; then
+		local mydb="nodbm"
+		use gdbm   && mydb="${mydb},gdbm"   || mydb="${mydb},nogdbm"
+		use berkdb && mydb="${mydb},berkdb" || mydb="${mydb},noberkdb"
+		myconf="${myconf} --with-database=${mydb}"
+	else
+		myconf="${myconf} --without-database"
+	fi
+
+	if use debug ; then
+		myconf="${myconf} --with-debug"
+		# bug #924339
+		append-flags -fno-strict-aliasing
+	else
+		myconf="${myconf} --with-optimization --with-cflags-debugging="
+	fi
+
+	use bignum && myconf="${myconf} --with-bignum=openssl" ||
+		myconf="${myconf} --with-bignum=no"
+
+	econf ${myconf} \
+		$(use_with gif ) \
+		$(use_with gpm ) \
+		$(use_with postgres postgresql ) \
+		$(use_with ldap ) \
+		$(use_with pop ) \
+		--prefix=/usr \
+		--with-unicode-internal \
+		--without-canna \
+		--with-ncurses \
+		--with-msw=no \
+		--with-mail-locking=flock \
+		--with-site-lisp=yes \
+		--with-site-modules=yes \
+		--enable-option-checking=no \
+		--with-last-packages=/usr/lib/xemacs
+}
+
+src_compile() {
+	# bug #959756
+	local -x CCACHE_DISABLE=1
+	emake EMACSLOADPATH="${S}"/lisp
+}
+
+src_install() {
+	emake prefix="${ED}"/usr \
+		mandir="${ED}"/usr/share/man/man1 \
+		infodir="${ED}"/usr/share/info \
+		libdir="${ED}"/usr/$(get_libdir) \
+		datadir="${ED}"/usr/share \
+		install
+
+	# Rename some applications installed in bin so that it is clear
+	# which application installed them and so that conflicting
+	# packages (emacs) can't clobber the actual applications.
+	# Addresses bug #62991.
+	for i in ctags etags gnuclient gnudoit gnuattach; do
+		mv "${ED}"/usr/bin/${i} "${ED}"/usr/bin/${i}-xemacs || die "mv ${i} failed"
+	done
+
+	# rename man pages
+	for i in ctags etags gnuserv gnuclient gnudoit gnuattach; do
+		mv "${ED}"/usr/share/man/man1/${i}{,-xemacs}.1 || die "mv ${i}.1 failed"
+	done
+
+	# install base packages directories
+	dodir /usr/lib/xemacs/xemacs-packages/
+	dodir /usr/lib/xemacs/site-packages/
+	dodir /usr/lib/xemacs/site-modules/
+	dodir /usr/lib/xemacs/site-lisp/
+	dodir /usr/lib/xemacs/mule-packages
+
+	# remove extraneous info files
+	cd "${ED}"/usr/share/info
+	rm -f dir info.info texinfo* termcap* standards*
+
+	cd "${S}"
+	dodoc CHANGES-* ChangeLog INSTALL Installation PROBLEMS README*
+
+	domenu "${S}"/etc/${PN}.desktop
+	newicon "${S}"/etc/${PN}-icon.xpm ${PN}.xpm
+}
+
+pkg_postinst() {
+	eselect emacs update ifunset
+	eselect gnuclient update ifunset
+	xdg_desktop_database_update
+
+	einfo "If you are upgrading from XEmacs 21.4 you should note the following"
+	einfo "incompatibilities:"
+	einfo "- Mule-UCS is no longer supported due to proper UTF-8 support in XEmacs 21.5"
+	einfo "- The X resource class has changed from Emacs to XEmacs,"
+	einfo "  settings in your .Xdefaults file should be updated accordingly."
+
+	if use xft;
+	then
+	  einfo "You have enabled Xft font support. Xft requires font names to be provided"
+	  einfo "in a different way, so you may need to adjust your .Xdefaults accordingly."
+	fi
+}
+
+pkg_postrm() {
+	eselect emacs update ifunset
+	eselect gnuclient update ifunset
+	xdg_desktop_database_update
+}
diff --git a/eclass/distutils-r1.eclass b/eclass/distutils-r1.eclass
index 8fc92cf4fca5c..5980cc47e5f74 100644
--- a/eclass/distutils-r1.eclass
+++ b/eclass/distutils-r1.eclass
@@ -415,6 +415,28 @@ unset -f _distutils_set_globals
 # }
 # @CODE
 
+# @ECLASS_VARIABLE: DISTUTILS_CONFIG_SETTINGS_JSON
+# @DEFAULT_UNSET
+# @DESCRIPTION:
+# The JSON object deserialized into config_settings dictionary passed
+# to the build backend.
+#
+# Allowed only for DISTUTILS_USE_PEP517=standalone.  Use DISTUTILS_ARGS
+# for other backends.
+#
+# Example:
+# @CODE
+# python_configure_all() {
+# 	DISTUTILS_CONFIG_SETTINGS_JSON='
+# 		{
+# 			"verbose": true,
+# 			"targets": ["foo", "bar"],
+# 			"build-type": "release"
+# 		}
+# 	'
+# }
+# @CODE
+
 # @FUNCTION: distutils_enable_sphinx
 # @USAGE: <subdir> [--no-autodoc | <plugin-pkgs>...]
 # @DESCRIPTION:
@@ -1197,6 +1219,12 @@ distutils_pep517_install() {
 			;;
 	esac
 
+	if [[ ${DISTUTILS_USE_PEP517} == standalone ]]; then
+		config_settings=${DISTUTILS_CONFIG_SETTINGS_JSON}
+	elif [[ -n ${DISTUTILS_CONFIG_SETTINGS_JSON} ]]; then
+		die "DISTUTILS_CONFIG_SETTINGS_JSON supported only for standalone backends"
+	fi
+
 	# https://pyo3.rs/latest/building-and-distribution.html#cross-compiling
 	if tc-is-cross-compiler; then
 		local -x PYO3_CROSS_LIB_DIR=${SYSROOT}/$(python_get_stdlib)
@@ -1486,8 +1514,8 @@ distutils-r1_run_phase() {
 
 	local -x PATH=${BUILD_DIR}/install${EPREFIX}/usr/bin:${PATH}
 	# Set up build environment, bug #513664.
-	local -x AR=${AR} CC=${CC} CPP=${CPP} CXX=${CXX}
-	tc-export AR CC CPP CXX
+	local -x AR=${AR} CC=${CC} CPP=${CPP} CXX=${CXX} PKG_CONFIG=${PKG_CONFIG}
+	tc-export AR CC CPP CXX PKG_CONFIG
 
 	# Perform additional environment modifications only for python_compile
 	# phase.  This is the only phase where we expect to be calling the Python
diff --git a/media-libs/openimageio/files/openimageio-3.0.8.1-avcodec_close.patch b/media-libs/openimageio/files/openimageio-3.0.8.1-avcodec_close.patch
new file mode 100644
index 0000000000000..190040e607582
--- /dev/null
+++ b/media-libs/openimageio/files/openimageio-3.0.8.1-avcodec_close.patch
@@ -0,0 +1,25 @@
+From 575a3ae620409971cf1693a802d062a6e75f1c69 Mon Sep 17 00:00:00 2001
+From: "Vlad (Kuzmin) Erium" <libalias@gmail.com>
+Date: Wed, 23 Jul 2025 19:13:57 +0900
+Subject: [PATCH] Replace avcodec_close with avcodec_free_context
+
+avcodec_close (AVCodecContext *avctx) removing in ffmpeg 7.2 and was deprecated for couple years
+
+Signed-off-by: Vlad (Kuzmin) Erium <libalias@gmail.com>
+---
+ src/ffmpeg.imageio/ffmpeginput.cpp | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/ffmpeg.imageio/ffmpeginput.cpp b/src/ffmpeg.imageio/ffmpeginput.cpp
+index 1e78f77c72..7cfaf601b2 100644
+--- a/src/ffmpeg.imageio/ffmpeginput.cpp
++++ b/src/ffmpeg.imageio/ffmpeginput.cpp
+@@ -581,7 +581,7 @@ bool
+ FFmpegInput::close(void)
+ {
+     if (m_codec_context)
+-        avcodec_close(m_codec_context);
++        avcodec_free_context(&m_codec_context);
+     if (m_format_context) {
+         avformat_close_input(&m_format_context);
+         av_free(m_format_context);  // will free m_codec and m_codec_context
diff --git a/media-libs/openimageio/openimageio-3.0.8.1-r2.ebuild b/media-libs/openimageio/openimageio-3.0.8.1-r2.ebuild
new file mode 100644
index 0000000000000..6b6eeffee9759
--- /dev/null
+++ b/media-libs/openimageio/openimageio-3.0.8.1-r2.ebuild
@@ -0,0 +1,448 @@
+# Copyright 1999-2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+PYTHON_COMPAT=( python3_{11..14} )
+
+TEST_OIIO_IMAGE_COMMIT="75099275c73a6937d40c69f9e14a006aa49fa201"
+TEST_OEXR_IMAGE_COMMIT="e38ffb0790f62f05a6f083a6fa4cac150b3b7452"
+inherit cuda cmake flag-o-matic python-single-r1 toolchain-funcs
+
+# TODO
+# investigate defaulting back to CMAKE_BUILD_TYPE=Release
+
+DESCRIPTION="A library for reading and writing images"
+HOMEPAGE="
+	https://sites.google.com/site/openimageio/
+	https://github.com/AcademySoftwareFoundation/OpenImageIO
+"
+SRC_URI="
+	https://github.com/AcademySoftwareFoundation/OpenImageIO/archive/v${PV}.tar.gz
+		-> ${P}.tar.gz
+	test? (
+		https://github.com/AcademySoftwareFoundation/OpenImageIO-images/archive/${TEST_OIIO_IMAGE_COMMIT}.tar.gz
+		 -> ${PN}-oiio-test-image-${TEST_OIIO_IMAGE_COMMIT}.tar.gz
+		https://github.com/AcademySoftwareFoundation/openexr-images/archive/${TEST_OEXR_IMAGE_COMMIT}.tar.gz
+		 -> ${PN}-oexr-test-image-${TEST_OEXR_IMAGE_COMMIT}.tar.gz
+		jpeg2k? (
+			https://www.itu.int/wftp3/Public/t/testsignal/SpeImage/T803/v2002_11/J2KP4files.zip
+		)
+		fits? (
+			https://www.cv.nrao.edu/fits/data/tests/ftt4b/file001.fits
+			https://www.cv.nrao.edu/fits/data/tests/ftt4b/file002.fits
+			https://www.cv.nrao.edu/fits/data/tests/ftt4b/file003.fits
+			https://www.cv.nrao.edu/fits/data/tests/ftt4b/file009.fits
+			https://www.cv.nrao.edu/fits/data/tests/ftt4b/file012.fits
+			https://www.cv.nrao.edu/fits/data/tests/pg93/tst0001.fits
+			https://www.cv.nrao.edu/fits/data/tests/pg93/tst0003.fits
+			https://www.cv.nrao.edu/fits/data/tests/pg93/tst0005.fits
+			https://www.cv.nrao.edu/fits/data/tests/pg93/tst0006.fits
+			https://www.cv.nrao.edu/fits/data/tests/pg93/tst0007.fits
+			https://www.cv.nrao.edu/fits/data/tests/pg93/tst0008.fits
+			https://www.cv.nrao.edu/fits/data/tests/pg93/tst0013.fits
+		)
+	)
+"
+S="${WORKDIR}/OpenImageIO-${PV}"
+
+LICENSE="Apache-2.0"
+SLOT="0/$(ver_cut 1-2)"
+KEYWORDS="~amd64 ~arm ~arm64 ~ppc64 ~riscv"
+
+X86_CPU_FEATURES=(
+	aes:aes
+	sse2:sse2
+	sse3:sse3
+	ssse3:ssse3
+	sse4_1:sse4.1
+	sse4_2:sse4.2
+	avx:avx
+	avx2:avx2
+	avx512f:avx512f
+	f16c:f16c
+)
+CPU_FEATURES=( "${X86_CPU_FEATURES[@]/#/cpu_flags_x86_}" )
+
+IUSE="cuda debug dicom doc ffmpeg fits gif gui jpeg2k jpegxl libcxx opencv openvdb ptex python raw test +tools +truetype ${CPU_FEATURES[*]%:*}"
+REQUIRED_USE="python? ( ${PYTHON_REQUIRED_USE} ) gui? ( tools ) test? ( tools truetype )"
+
+RESTRICT="!test? ( test )"
+
+BDEPEND="
+	jpeg2k? ( app-arch/unzip )
+	doc? (
+		app-text/doxygen
+		dev-texlive/texlive-bibtexextra
+		dev-texlive/texlive-fontsextra
+		dev-texlive/texlive-fontutils
+		dev-texlive/texlive-latex
+		dev-texlive/texlive-latexextra
+	)
+"
+
+# >=media-libs/libuhdr-1.3
+RDEPEND="
+	app-arch/bzip2:=
+	dev-cpp/robin-map
+	dev-libs/pugixml
+	media-libs/libheif:=
+	media-libs/libjpeg-turbo:=
+	media-libs/libpng:=
+	media-libs/libwebp:=
+	media-libs/opencolorio:=
+	media-libs/openexr:=
+	media-libs/tiff:=
+	virtual/zlib:=
+	dicom? ( sci-libs/dcmtk )
+	ffmpeg? ( media-video/ffmpeg:= )
+	fits? ( sci-libs/cfitsio:= )
+	gif? ( media-libs/giflib:= )
+	jpeg2k? ( media-libs/openjpeg:= )
+	jpegxl? ( media-libs/libjxl:= )
+	opencv? ( media-libs/opencv:= )
+	openvdb? (
+		dev-cpp/tbb:=
+		media-gfx/openvdb:=
+	)
+	ptex? ( media-libs/ptex:= )
+	python? (
+		${PYTHON_DEPS}
+		$(python_gen_cond_dep '
+			dev-python/numpy:=[${PYTHON_USEDEP}]
+			dev-python/pybind11[${PYTHON_USEDEP}]
+		')
+	)
+	gui? (
+		media-libs/libglvnd
+		dev-qt/qtbase:6[gui,widgets,opengl]
+	)
+	raw? ( media-libs/libraw:= )
+	truetype? ( media-libs/freetype )
+"
+DEPEND="
+	dev-libs/imath:=
+	dev-libs/libfmt:=
+	${RDEPEND}
+	test? ( media-fonts/droid )
+"
+
+DOCS=(
+	CHANGES.md
+	CREDITS.md
+	README.md
+)
+
+PATCHES=(
+	# "${FILESDIR}/${PN}-2.5.8.0-fix-tests.patch"
+	"${FILESDIR}/${PN}-2.5.12.0-heif-find-fix.patch"
+	"${FILESDIR}/${PN}-2.5.18.0-tests-optional.patch"
+	# in src_prepare
+	# "${FILESDIR}/${PN}-2.5.12.0_heif_test.patch"
+	# Fix bug 965279: https://bugs.gentoo.org/965279
+	"${FILESDIR}/${PN}-3.0.8.1-libheif_new.patch"
+	# Fix bug 965569: https://bugs.gentoo.org/965569
+	"${FILESDIR}/${PN}-3.0.8.1-avcodec_close.patch"
+)
+
+pkg_setup() {
+	use python && python-single-r1_pkg_setup
+}
+
+src_prepare() {
+	if ! use dicom; then
+		rm "src/dicom.imageio" -r || die
+	fi
+
+	if ! use gif; then
+		rm src/gif.imageio -r || die
+	fi
+
+	if ! use jpeg2k; then
+		rm src/jpeg2000.imageio -r || die
+	fi
+
+	if ! use raw; then
+		rm src/raw.imageio -r || die
+	fi
+
+	cmake_src_prepare
+	cmake_comment_add_subdirectory src/fonts
+
+	if use test ; then
+		ln -s "${WORKDIR}/OpenImageIO-images-${TEST_OIIO_IMAGE_COMMIT}" "${WORKDIR}/oiio-images" || die
+		ln -s "${WORKDIR}/openexr-images-${TEST_OEXR_IMAGE_COMMIT}" "${WORKDIR}/openexr-images" || die
+
+		if use fits; then
+			mkdir -p "${WORKDIR}/fits-images/"{ftt4b,pg93} || die
+			for a in ${A}; do
+				if [[ "${a}" == file*.fits ]]; then
+					ln -s "${DISTDIR}/${a}" "${WORKDIR}/fits-images/ftt4b/" || die
+				fi
+				if [[ "${a}" == tst*.fits ]]; then
+					ln -s "${DISTDIR}/${a}" "${WORKDIR}/fits-images/pg93/" || die
+				fi
+			done
+		fi
+
+		if use jpeg2k; then
+			ln -s "${WORKDIR}/J2KP4files" "${WORKDIR}/j2kp4files_v1_5" || die
+		fi
+
+		cp testsuite/heif/ref/out-libheif1.1{2,5}-orient.txt || die
+		eapply "${FILESDIR}/${PN}-2.5.12.0_heif_test.patch"
+	fi
+
+	mkdir "${T}/cmake" || die
+
+	local libdir="${ESYSROOT}/usr/$(get_libdir)"
+
+	# generate our own WebPConfig.cmake via pkg-config # 937031
+	cat <<-EOF > "${T}/cmake/WebPConfig.cmake" || die
+	set(WebP_VERSION $(pkg-config --modversion libwebp))
+	set(WEBP_VERSION \${WebP_VERSION})
+
+	set_and_check(WebP_INCLUDE_DIR "$(pkg-config --variable includedir libwebp)")
+	set(WebP_INCLUDE_DIRS \${WebP_INCLUDE_DIR})
+	set(WEBP_INCLUDE_DIRS \${WebP_INCLUDE_DIR})
+	set(WebP_LIBRARIES "webp")
+	set(WEBP_LIBRARIES "\${WebP_LIBRARIES}")
+
+	# Create imported target WebP::sharpyuv
+	add_library(WebP::sharpyuv STATIC IMPORTED)
+
+	set_target_properties(WebP::sharpyuv PROPERTIES
+		INTERFACE_INCLUDE_DIRECTORIES "\${WebP_INCLUDE_DIR};\${WebP_INCLUDE_DIR}/webp"
+		INTERFACE_LINK_LIBRARIES "m"
+	)
+
+	# Create imported target WebP::webp
+	add_library(WebP::webp STATIC IMPORTED)
+
+	set_target_properties(WebP::webp PROPERTIES
+		INTERFACE_INCLUDE_DIRECTORIES "\${WebP_INCLUDE_DIR}"
+		INTERFACE_LINK_LIBRARIES "WebP::sharpyuv;Threads::Threads;m"
+	)
+
+	# Create imported target WebP::webpdemux
+	add_library(WebP::webpdemux STATIC IMPORTED)
+
+	set_target_properties(WebP::webpdemux PROPERTIES
+		INTERFACE_INCLUDE_DIRECTORIES "\${WebP_INCLUDE_DIR}"
+		INTERFACE_LINK_LIBRARIES "WebP::webp"
+	)
+
+	# Import target "WebP::webp" for configuration "RelWithDebInfo"
+	set_property(TARGET WebP::webp APPEND PROPERTY IMPORTED_CONFIGURATIONS RELWITHDEBINFO)
+	set_target_properties(WebP::webp PROPERTIES
+		IMPORTED_LINK_INTERFACE_LANGUAGES_RELWITHDEBINFO "C"
+		IMPORTED_LOCATION_RELWITHDEBINFO "${libdir}/libwebp.so"
+	)
+
+	list(APPEND _cmake_import_check_targets WebP::webp )
+	list(APPEND _cmake_import_check_files_for_WebP::webp "${libdir}/libwebp.so" )
+
+	# Import target "WebP::webpdemux" for configuration "RelWithDebInfo"
+	set_property(TARGET WebP::webpdemux APPEND PROPERTY IMPORTED_CONFIGURATIONS RELWITHDEBINFO)
+	set_target_properties(WebP::webpdemux PROPERTIES
+		IMPORTED_LINK_INTERFACE_LANGUAGES_RELWITHDEBINFO "C"
+		IMPORTED_LOCATION_RELWITHDEBINFO "${libdir}/libwebpdemux.so"
+	)
+
+	list(APPEND _cmake_import_check_targets WebP::webpdemux )
+	list(APPEND _cmake_import_check_files_for_WebP::webpdemux "${libdir}/libwebpdemux.so" )
+
+	# Import target "WebP::sharpyuv" for configuration "RelWithDebInfo"
+	set_property(TARGET WebP::sharpyuv APPEND PROPERTY IMPORTED_CONFIGURATIONS RELWITHDEBINFO)
+	set_target_properties(WebP::sharpyuv PROPERTIES
+		IMPORTED_LINK_INTERFACE_LANGUAGES_RELWITHDEBINFO "C"
+		IMPORTED_LOCATION_RELWITHDEBINFO "${libdir}/libsharpyuv.so"
+	)
+
+	list(APPEND _cmake_import_check_targets WebP::sharpyuv )
+	list(APPEND _cmake_import_check_files_for_WebP::sharpyuv "${libdir}/libsharpyuv.so" )
+
+	check_required_components(WebP)
+	EOF
+}
+
+src_configure() {
+	# Build with SIMD support
+	local cpufeature
+	local mysimd=()
+	for cpufeature in "${CPU_FEATURES[@]}"; do
+		use "${cpufeature%:*}" && mysimd+=("${cpufeature#*:}")
+	done
+
+	# If no CPU SIMDs were used, completely disable them
+	[[ -z ${mysimd[*]} ]] && mysimd=("0")
+
+	# This is currently needed on arm64 to get the NEON SIMD wrapper to compile the code successfully
+	# Even if there are no SIMD features selected, it seems like the code will turn on NEON support if it is available.
+	use arm64 && append-flags -flax-vector-conversions
+
+	append-cflags "$(usex debug '-DDEBUG' '-DNDEBUG')"
+	append-cxxflags "$(usex debug '-DDEBUG' '-DNDEBUG')"
+
+	local mycmakeargs=(
+		-DVERBOSE="no"
+		-DLINKSTATIC="no"
+
+		-DTEX_BATCH_SIZE="16" # AVX512 -> 16
+		-DSTOP_ON_WARNING="no"
+
+		-DCMAKE_CXX_STANDARD="17"
+		-DDOWNSTREAM_CXX_STANDARD="17"
+
+		-DCMAKE_UNITY_BUILD=OFF
+		# -DCMAKE_UNITY_BUILD_MODE="BATCH"
+		# -DCMAKE_UNITY_BUILD_BATCH_SIZE="$(nproc)"
+
+		-DBUILD_DOCS="$(usex doc)"
+		# -DBUILD_OIIOUTIL_ONLY="no"
+		-DBUILD_TESTING="$(usex test)"
+
+		-DINSTALL_FONTS="no"
+		-DINSTALL_DOCS="$(usex doc)"
+
+		-DENABLE_DCMTK="$(usex dicom)"
+		-DENABLE_FFmpeg="$(usex ffmpeg)"
+		-DENABLE_FITS="$(usex fits)"
+		-DENABLE_FREETYPE="$(usex truetype)"
+		-DENABLE_GIF="$(usex gif)"
+		-DENABLE_LibRaw="$(usex raw)"
+		-DENABLE_Nuke="no" # not in Gentoo
+		-DENABLE_OpenCV="$(usex opencv)"
+		-DENABLE_OpenJPEG="$(usex jpeg2k)"
+		-DENABLE_OpenVDB="$(usex openvdb)"
+		-DENABLE_TBB="$(usex openvdb)"
+		-DENABLE_Ptex="$(usex ptex)"
+
+		-DENABLE_libuhdr="no" # not in Gentoo
+		-DENABLE_WebP="yes" # missing cmake files
+
+		-DOIIO_BUILD_TESTS="$(usex test)"
+		-DOIIO_BUILD_TOOLS="$(usex tools)"
+		-DOIIO_DOWNLOAD_MISSING_TESTDATA="no"
+		-DOIIO_INTERNALIZE_FMT="no"
+		-DOIIO_USE_CUDA="$(usex cuda)"
+		# -DOIIO_USE_EXR_C_API="yes"
+
+		-DOPENIMAGEIO_CONFIG_DO_NOT_FIND_IMATH="yes"
+
+		# -DOpenImageIO_ALWAYS_PREFER_CONFIG="yes" # breaks openexr detection
+		-DOpenImageIO_BUILD_STATIC_UTIL_LIBRARY="no"
+
+		-DUSE_CCACHE="no"
+		-DUSE_EXTERNAL_PUGIXML="yes"
+		-DUSE_JXL="$(usex jpegxl)"
+		-DUSE_R3DSDK="no" # not in Gentoo
+		-DUSE_PYTHON="$(usex python)"
+		-DUSE_QT="$(usex gui)"
+		-DUSE_SIMD="$(local IFS=','; echo "${mysimd[*]}")"
+
+		-DWebP_DIR="${T}/cmake"
+	)
+
+	if use gui; then
+		mycmakeargs+=(
+			-DUSE_IV="yes"
+			-DUSE_OPENGL="yes"
+			# -DUSE_CCACHE="yes"
+			# needs local -x CCACHE_CPP2=1
+			# CXX_COMPILER_LAUNCHER
+		)
+	fi
+
+	if use python; then
+		mycmakeargs+=(
+			"-DPYTHON_VERSION=${EPYTHON#python}"
+			"-DPYTHON_SITE_DIR=$(python_get_sitedir)"
+		)
+	fi
+
+	if use test; then
+		mycmakeargs+=(
+			-DENABLE_LIBRAW="$(usex raw)"
+			-DENABLE_OPENJPEG="$(usex jpeg2k)"
+			-DENABLE_PTEX="$(usex ptex)"
+		)
+	fi
+
+	# checks CMAKE_COMPILER_IS_CLANG
+	if tc-is-clang; then
+		mycmakeargs+=(
+			-DUSE_LIBCPLUSPLUS="$(usex libcxx)"
+		)
+	fi
+
+	cmake_src_configure
+}
+
+src_test() {
+	# A lot of tests needs to have access to the installed data files.
+	# So install them into the image directory now.
+	DESTDIR="${T}" cmake_build install
+
+	if use cuda; then
+		cuda_add_sandbox -w
+		addwrite "/proc/self/task/"
+		addpredict "/dev/char/"
+	fi
+
+	CMAKE_SKIP_TESTS=(
+		"-broken$"
+
+		"texture-interp-bilinear.batch$"
+		"texture-interp-closest.batch$"
+		"texture-levels-stochaniso.batch$"
+		"texture-levels-stochmip.batch$"
+
+		"texture-mip-onelevel.batch$"
+		"texture-mip-stochastictrilinear.batch$"
+		"texture-mip-stochasticaniso.batch$"
+
+		"^python-imagebufalgo$"
+
+		"^bmp$"
+		"^dds$"
+		"^ico$"
+		"^jpeg2000$"
+		"^psd$"
+		"^ptex$"
+	)
+
+	sed -e "s#../../../testsuite#../../../OpenImageIO-${PV}/testsuite#g" \
+		-i "${CMAKE_USE_DIR}/testsuite/python-imagebufalgo/ref/out.txt" || die
+
+	# NOTE testsuite/runtest.py
+	local -x CI=true
+	# local -x OPENIMAGEIO_CUDA=0 # prevent trying to access gpu devices
+	# local -x OIIO_USE_CUDA=0
+	local -x CMAKE_PREFIX_PATH="${T}/usr"
+	local -x LD_LIBRARY_PATH
+	LD_LIBRARY_PATH="${T}/usr/$(get_libdir)"
+	# local -x OPENIMAGEIO_DEBUG_FILE
+	local -x OPENIMAGEIO_DEBUG=0
+
+	# find ${CMAKE_USE_DIR}/src/fonts -mindepth 1 -type d
+	local -x OPENIMAGEIO_FONTS="${CMAKE_USE_DIR}/src/fonts/Droid_Serif"
+
+	if use python; then
+		local -x PYTHONPATH="${T}$(python_get_sitedir)"
+	fi
+
+	cmake_src_test
+
+	# Clean up the image directory for src_install
+	rm -fr "${T:?}"/usr || die
+}
+
+src_install() {
+	cmake_src_install
+
+	# remove Windows loader file
+	if use python; then
+		rm "${D}$(python_get_sitedir)/__init__.py" || die
+	fi
+}