diff --git a/sci-mathematics/yafu/files/fix-Makefile.patch b/sci-mathematics/yafu/files/yafu-1.34.3-Makefile.patch
similarity index 63%
rename from sci-mathematics/yafu/files/fix-Makefile.patch
rename to sci-mathematics/yafu/files/yafu-1.34.3-Makefile.patch
index 82b8e0d7d2ff..bee579150c9d 100644
--- a/sci-mathematics/yafu/files/fix-Makefile.patch
+++ b/sci-mathematics/yafu/files/yafu-1.34.3-Makefile.patch
@@ -1,5 +1,5 @@
---- Makefile.orig	2013-03-17 11:20:40.248683894 +0400
-+++ Makefile	2013-03-17 11:20:47.352683657 +0400
+--- a/Makefile
++++ b/Makefile
 @@ -87,7 +87,7 @@ ifeq ($(CC),icc)
  	CFLAGS += -mtune=core2 -march=core2
  endif
diff --git a/sci-mathematics/yafu/metadata.xml b/sci-mathematics/yafu/metadata.xml
index 651621cc9277..f07f2757aeb5 100644
--- a/sci-mathematics/yafu/metadata.xml
+++ b/sci-mathematics/yafu/metadata.xml
@@ -1,14 +1,14 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
 <pkgmetadata>
-  <maintainer type="person">
-    <email>patrick@gentoo.org</email>
-    <name>Patrick Lauer</name>
-  </maintainer>
-  <use>
-    <flag name="sieve">Use msieve for the sieving steps of NFS</flag>
-  </use>
-  <upstream>
-    <remote-id type="sourceforge">yafu</remote-id>
-  </upstream>
+	<maintainer type="person">
+		<email>patrick@gentoo.org</email>
+		<name>Patrick Lauer</name>
+	</maintainer>
+	<use>
+		<flag name="sieve">Use msieve for the sieving steps of NFS</flag>
+	</use>
+	<upstream>
+		<remote-id type="sourceforge">yafu</remote-id>
+	</upstream>
 </pkgmetadata>
diff --git a/sci-mathematics/yafu/yafu-1.34.3.ebuild b/sci-mathematics/yafu/yafu-1.34.3.ebuild
index cf1be408e987..e48b2e4b2059 100644
--- a/sci-mathematics/yafu/yafu-1.34.3.ebuild
+++ b/sci-mathematics/yafu/yafu-1.34.3.ebuild
@@ -1,12 +1,11 @@
-# Copyright 1999-2016 Gentoo Foundation
+# Copyright 1999-2021 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
-EAPI=5
+EAPI=7
 
-inherit eutils versionator
-
-MY_PV="$(get_version_component_range 1-2)"
+inherit flag-o-matic
 
+MY_PV="$(ver_cut 1-2)"
 DESCRIPTION="Yet another factoring utility"
 HOMEPAGE="https://sourceforge.net/projects/yafu/"
 SRC_URI="mirror://sourceforge/${PN}/${MY_PV}/${PN}-${MY_PV}-src.zip"
@@ -14,42 +13,47 @@ SRC_URI="mirror://sourceforge/${PN}/${MY_PV}/${PN}-${MY_PV}-src.zip"
 SLOT="0"
 LICENSE="public-domain"
 KEYWORDS="~amd64 ~x86"
-# nfs is overloaded, so using less confusing sieve here
 IUSE="+sieve"
 
 DEPEND="
 	dev-libs/gmp:0=
 	sci-mathematics/gmp-ecm
 	sieve? (
+		sci-mathematics/ggnfs
 		sci-mathematics/msieve
-		sci-mathematics/ggnfs )"
+	)"
 RDEPEND="${DEPEND}"
+BDEPEND="app-arch/unzip"
+
+PATCHES=( "${FILESDIR}"/${P}-Makefile.patch )
 
 src_prepare() {
-	epatch "${FILESDIR}/fix-Makefile.patch"
-	# This is not nice. But then the Makefile is quite special :)
-	sed -i -e 's:../gmp/include:gmp:' Makefile 		|| die "Failed to rectify things"
-	sed -i -e 's:../gmp-ecm/include:gmp-ecm:' Makefile 	|| die "Failed to rectify things"
-	sed -i -e 's:LIBS += -L../:# LIBS += -L../:g' Makefile	|| die "Failed to rectify things"
-	sed -i -e 's:\"config.h\":<gmp-ecm/config.h>:g' top/driver.c	|| die "Failed to rectify things"
-	sed -i -e 's:# LIBS += -L../msieve/lib/linux/x86_64:LIBS += -lmsieve -lz -ldl:' Makefile	|| die "Failed to rectify things"
-	sed -i -e 's:CFLAGS = -g:#CFLAGS = -g:' Makefile	|| die "Failed to rectify things"
-	sed -i -e '/$(LIBS)$/s:$(CC):$(CC) $(LDFLAGS):g' Makefile || die
+	default
+	sed -i \
+		-e 's:../gmp/include:gmp:' \
+		-e 's:../gmp-ecm/include:gmp-ecm:' \
+		-e 's:# LIBS += -L../msieve/lib/linux/x86_64:LIBS += -lmsieve -lz -ldl:' \
+		-e 's:CFLAGS = -g:#CFLAGS = -g:' \
+		-e '/$(LIBS)$/s:$(CC):$(CC) $(LDFLAGS):g' Makefile || die
+	sed -i -e 's:\"config.h\":<gmp-ecm/config.h>:g' top/driver.c || die
 
 	# proper ggnfs default path
-	sed -i -e 's~strcpy(fobj->nfs_obj.ggnfs_dir,"./");~strcpy(fobj->nfs_obj.ggnfs_dir,"/usr/bin/");~' factor/factor_common.c || die "Failed to rectify things"
+	sed -i -e 's~strcpy(fobj->nfs_obj.ggnfs_dir,"./");~strcpy(fobj->nfs_obj.ggnfs_dir,"/usr/bin/");~' factor/factor_common.c || die
+}
+
+src_configure() {
+	append-cflags -fcommon
+	default
 }
 
 src_compile() {
-	local VAR=""
-	# hmm, not that useful:
-	#VAR="TIMING=1 "
-	use sieve && VAR+="NFS=1"
+	local VAR
+	use sieve && VAR="NFS=1"
 	use amd64 && emake $VAR x86_64
 	use x86 && emake $VAR x86
 }
 
 src_install() {
-	dobin "${S}/yafu"
+	dobin "${S}"/yafu
 	dodoc docfile.txt README yafu.ini
 }