diff --git a/media-gfx/librecad/files/librecad-2.1.3-boost-1.76.patch b/media-gfx/librecad/files/librecad-2.1.3-boost-1.76.patch
new file mode 100644
index 0000000000000..2500bab79b199
--- /dev/null
+++ b/media-gfx/librecad/files/librecad-2.1.3-boost-1.76.patch
@@ -0,0 +1,29 @@
+From 1fd07fcd847659d518efa0897a9f603de83fe362 Mon Sep 17 00:00:00 2001
+From: Jiri Slaby <jslaby@suse.cz>
+Date: Tue, 4 May 2021 09:25:03 +0200
+Subject: [PATCH] add boost tuple include to fix build
+
+With boost 1.76, we see:
+lib/engine/rs_ellipse.cpp:70:15: error: 'tuple' in namespace 'boost::math' does not name a template type
+   70 |  boost::math::tuple<double, double, double> operator()(double const& z) const {
+      |               ^~~~~
+
+Fix this by including the proper boost header.
+---
+ librecad/src/lib/engine/rs_ellipse.cpp | 3 +++
+ 1 file changed, 3 insertions(+)
+
+diff --git a/librecad/src/lib/engine/rs_ellipse.cpp b/librecad/src/lib/engine/rs_ellipse.cpp
+index 291f734ea..d47bf6ca4 100644
+--- a/librecad/src/lib/engine/rs_ellipse.cpp
++++ b/librecad/src/lib/engine/rs_ellipse.cpp
+@@ -48,6 +48,9 @@
+ #include <boost/version.hpp>
+ #include <boost/math/tools/roots.hpp>
+ #include <boost/math/special_functions/ellint_2.hpp>
++#if BOOST_VERSION > 104500
++#include <boost/math/tools/tuple.hpp>
++#endif
+ #endif
+ 
+ namespace{
diff --git a/media-gfx/librecad/librecad-2.1.3-r5.ebuild b/media-gfx/librecad/librecad-2.1.3-r5.ebuild
index bc56b908be42c..7b21b0e12ca45 100644
--- a/media-gfx/librecad/librecad-2.1.3-r5.ebuild
+++ b/media-gfx/librecad/librecad-2.1.3-r5.ebuild
@@ -1,4 +1,4 @@
-# Copyright 1999-2020 Gentoo Authors
+# Copyright 1999-2021 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 EAPI=7
@@ -14,9 +14,6 @@ SLOT="0"
 KEYWORDS="amd64 ~ppc64 x86 ~amd64-linux ~x86-linux"
 IUSE="debug doc tools"
 
-BDEPEND="
-	dev-qt/linguist-tools:5
-"
 RDEPEND="
 	dev-cpp/muParser
 	dev-libs/boost:=
@@ -31,13 +28,17 @@ DEPEND="${RDEPEND}
 	dev-qt/qthelp:5
 	dev-qt/qtxml:5
 "
+BDEPEND="
+	dev-qt/linguist-tools:5
+"
 
 S="${WORKDIR}/LibreCAD-${PV}"
 
 PATCHES=(
 	"${FILESDIR}/${P}-qt-5.11.patch"
 	"${FILESDIR}/${P}-gcc-9.patch"
-	"${FILESDIR}/${P}-qt-5.15.patch" # pending upstream PR#1224
+	"${FILESDIR}/${P}-qt-5.15.patch"
+	"${FILESDIR}/${P}-boost-1.76.patch" # bug 788706, upstream PR#1345
 )
 
 src_configure() {