diff --git a/sci-electronics/klayout/Manifest b/sci-electronics/klayout/Manifest
index 0017ec4b0a6dc..a3c569278cebb 100644
--- a/sci-electronics/klayout/Manifest
+++ b/sci-electronics/klayout/Manifest
@@ -1 +1,2 @@
+DIST klayout-0.29.11.tar.gz 97526183 BLAKE2B 6da5c4590ae14c46f677b0e87fd001c89731db15abcbce42c3a22844a2277be7998c80cf8e39f0df8d3bdcc00ac39290fab87973ec3cf6aa21d4967f047ef143 SHA512 a03bc5e3ca612e0dab894a193e7f942ef4fb8860364fcdda2128b55fd81c82eb2c8122a1e340c03097a9def7942d151ba115def8322e3c103fcec09d4849f6dd
 DIST klayout-0.29.7.tar.gz 97112729 BLAKE2B 3e6d97bcbef5a1ef34ab6ac035db88dfa7f590ef7ab5d3b6312248244cbe4538407db0278b6c7dc2f0a5a4a966d21ee60d1f11200327773979852ecb835ec078 SHA512 361337d028b8266abd2c5114643a7b2074c794f5685b336658168f09df1f3e4826de2d3cb1e094bd2f08616d6f0be78c8f6b44144c74367dcaf65785476ab8ae
diff --git a/sci-electronics/klayout/klayout-0.29.11.ebuild b/sci-electronics/klayout/klayout-0.29.11.ebuild
new file mode 100644
index 0000000000000..7dd60f77e4372
--- /dev/null
+++ b/sci-electronics/klayout/klayout-0.29.11.ebuild
@@ -0,0 +1,91 @@
+# Copyright 1999-2025 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+EAPI=8
+
+RUBY_OPTIONAL=no
+USE_RUBY="ruby32"
+# note: define maximally ONE implementation here
+
+PYTHON_COMPAT=( python3_{11,12,13} )
+
+inherit toolchain-funcs python-single-r1 ruby-ng
+
+if [[ ${PV} = 9999* ]]; then
+	EGIT_REPO_URI="https://github.com/klayoutmatthias/${PN}.git"
+	inherit git-r3
+	EGIT_CHECKOUT_DIR=${WORKDIR}/all/${P}
+else
+	SRC_URI="https://www.klayout.org/downloads/source/${P}.tar.gz"
+	KEYWORDS="~amd64 ~x86"
+fi
+
+DESCRIPTION="Viewer and editor for GDS and OASIS integrated circuit layouts"
+HOMEPAGE="https://www.klayout.de/"
+LICENSE="GPL-2"
+SLOT="0"
+REQUIRED_USE=${PYTHON_REQUIRED_USE}
+
+RDEPEND="
+	dev-qt/designer:5
+	dev-qt/qtcore:5
+	dev-qt/qtgui:5
+	dev-qt/qtmultimedia:5[widgets]
+	dev-qt/qtnetwork:5[ssl]
+	dev-qt/qtprintsupport:5
+	dev-qt/qtsql:5
+	dev-qt/qtsvg:5
+	dev-qt/qttest:5
+	dev-qt/qtwidgets:5
+	dev-qt/qtxml:5
+	dev-qt/qtxmlpatterns:5
+	dev-libs/libgit2:=
+	sys-libs/zlib
+	${PYTHON_DEPS}
+	$(ruby_implementations_depend)
+"
+DEPEND="${RDEPEND}"
+
+pkg_setup() {
+	python-single-r1_pkg_setup
+	ruby-ng_pkg_setup
+}
+
+each_ruby_configure() {
+	tc-export CC CXX AR LD RANLIB
+	export CFLAGS CXXFLAGS
+	./build.sh \
+		-expert \
+		-dry-run \
+		-qmake "$EPREFIX/usr/$(get_libdir)/qt5/bin/qmake" \
+		-ruby "${RUBY}" \
+		-python "${PYTHON}" \
+		-build . \
+		-bin "${T}/bin" \
+		-rpath "$EPREFIX/usr/$(get_libdir)/klayout" \
+		-option "${MAKEOPTS}" \
+		-with-qtbinding \
+		-without-64bit-coord \
+		-qt5 || die "Configuration failed"
+}
+
+each_ruby_compile() {
+	emake all
+}
+
+each_ruby_install() {
+	emake install
+
+	cd "${T}/bin" || die
+
+	dodir "/usr/$(get_libdir)/klayout"
+	mv lib* lay_plugins db_plugins "${ED}/usr/$(get_libdir)/klayout/" || die
+
+	mkdir -p "${D}/$(python_get_sitedir)" || die
+	mv pymod/* "${D}/$(python_get_sitedir)/" || die
+	rmdir pymod || die
+
+	dobin *
+
+	python_optimize
+}