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diff --git a/eclass/ffmpeg-compat.eclass b/eclass/ffmpeg-compat.eclass
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+++ b/eclass/ffmpeg-compat.eclass
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+# Copyright 2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+# @ECLASS: ffmpeg-compat.eclass
+# @MAINTAINER:
+# Ionen Wolkens <ionen@gentoo.org>
+# @AUTHOR:
+# Ionen Wolkens <ionen@gentoo.org>
+# @SUPPORTED_EAPIS: 8
+# @BLURB: Helper functions to link with slotted ffmpeg-compat libraries
+# @DESCRIPTION:
+# To use this, run ``ffmpeg_compat_setup <slot>`` before packages use
+# pkg-config, depend on media-video/ffmpeg-compat:<slot>=, and ensure
+# usage of both pkg-config --cflags and --libs (which adds -Wl,-rpath
+# to find libraries at runtime).
+#
+# This eclass is intended as a quick-to-setup alternative to setting
+# an upper bound on ffmpeg for packages broken with the latest version,
+# and thus allow users to upgrade their normal ffmpeg.
+#
+# This should still be a temporary measure, and it is recommended to
+# keep migration bugs open rather than consider this eclass as being
+# the "fix".
+#
+# Unlike LLVM_SLOT-style, this does not have USE to select the slot
+# and should instead pick only the highest one usable until package
+# is fixed and can use non-slotted ffmpeg again.
+#
+# Do *not* use both like ``|| ( <ffmpeg-<ver> ffmpeg-compat:<slot> )``,
+# the package manager cannot know which version it linked against
+# without USE flags.  Unfortunately means a period where users may
+# have two identical versions in stable before the newest major version
+# is stabilized, but idea is to not mangle normal ffmpeg with slotting
+# logic and make this an isolated temporary deal.
+
+case ${EAPI} in
+	8) ;;
+	*) die "${ECLASS}: EAPI ${EAPI:-0} not supported" ;;
+esac
+
+if [[ -z ${_FFMPEG_COMPAT_ECLASS} ]]; then
+_FFMPEG_COMPAT_ECLASS=1
+
+# @FUNCTION: ffmpeg_compat_get_prefix
+# @USAGE: <slot>
+# @DESCRIPTION:
+# Return prefix of the installed ffmpeg-compat:<slot>.  Binaries like
+# ffmpeg will be found under <prefix>/bin if needed.
+ffmpeg_compat_get_prefix() {
+	(( ${#} == 1 )) || die "Usage: ${FUNCNAME} <slot>"
+
+	echo "${EPREFIX}/usr/lib/ffmpeg${1}"
+}
+
+# @FUNCTION: ffmpeg_compat_setup
+# @USAGE: <slot>
+# @DESCRIPTION:
+# Add ESYSROOT's ffmpeg-compat:<slot> to PKG_CONFIG_PATH for the
+# current ABI.
+ffmpeg_compat_setup() {
+	(( ${#} == 1 )) || die "Usage: ${FUNCNAME} <slot>"
+
+	: "${SYSROOT}$(ffmpeg_compat_get_prefix "${1}")/$(get_libdir)/pkgconfig"
+	export PKG_CONFIG_PATH=${_}:${PKG_CONFIG_PATH}
+}
+
+fi