diff --git a/math/singular/Makefile b/math/singular/Makefile
index c9fa418fe200..a3bb225ccf0c 100644
--- a/math/singular/Makefile
+++ b/math/singular/Makefile
@@ -2,7 +2,7 @@
 
 PORTNAME=	singular
 DISTVERSIONPREFIX=	Release-
-DISTVERSION=	4-1-3p2
+DISTVERSION=	4-2-0
 CATEGORIES=	math
 #MASTER_SITES=	ftp://jim.mathematik.uni-kl.de/pub/Math/Singular/SOURCES/${PORTVERSION:C/\./-/g}/
 
@@ -29,15 +29,21 @@ SHEBANG_FILES=	Singular/surfex \
 		libpolys/libpolys-config.in \
 		libsingular-config.in
 
-OPTIONS_DEFINE=		NTL
-OPTIONS_DEFAULT=	NTL
+OPTIONS_DEFINE=		FLINT NTL
+OPTIONS_DEFAULT=	FLINT NTL
 OPTIONS_SUB=		yes
+
+FLINT_DESC=		Use FLINT library
+FLINT_CONFIGURE_ON=	--with-flint=${LOCALBASE}
+FLINT_CONFIGURE_OFF=	--with-flint=no
+FLINT_LIB_DEPENDS=	libflint.so:math/flint2
+
 NTL_DESC=		Use NTL library
+NTL_USES=		compiler:c11
+NTL_CONFIGURE_ON=	--with-ntl=${LOCALBASE}
+NTL_CONFIGURE_OFF=	--with-ntl=no
 NTL_LIB_DEPENDS=	libntl.so:math/ntl	\
 			libcddgmp.so:math/cddlib
-NTL_CONFIGURE_ON=	--with-ntl=${LOCALBASE} --with-flint=no
-NTL_CONFIGURE_OFF=	--with-ntl=no
-NTL_USES=		compiler:c11
 
 # not a shebang but "/bin/bash" is hardcoded in some files
 post-patch:
diff --git a/math/singular/distinfo b/math/singular/distinfo
index f5be228e40d4..0147a2c35cd8 100644
--- a/math/singular/distinfo
+++ b/math/singular/distinfo
@@ -1,3 +1,3 @@
-TIMESTAMP = 1599325700
-SHA256 (Singular-Singular-Release-4-1-3p2_GH0.tar.gz) = 08f11f5f1f1570f85413567057cc1d3f42ab03d345bc08e459cc91bf110d8770
-SIZE (Singular-Singular-Release-4-1-3p2_GH0.tar.gz) = 12779738
+TIMESTAMP = 1608880139
+SHA256 (Singular-Singular-Release-4-2-0_GH0.tar.gz) = bdfe6fea1b43adc028f72b93c9590d35308572d59012947ac51ef3e0dc4cbd08
+SIZE (Singular-Singular-Release-4-2-0_GH0.tar.gz) = 12847369
diff --git a/math/singular/pkg-plist b/math/singular/pkg-plist
index 863f0e9c3027..71d5a063272b 100644
--- a/math/singular/pkg-plist
+++ b/math/singular/pkg-plist
@@ -7,6 +7,7 @@ include/factory/cf_gmp.h
 include/factory/factory.h
 include/factory/factoryconf.h
 include/factory/globaldefs.h
+include/factory/si_log2.h
 include/factory/templates/ftmpl_afactor.h
 include/factory/templates/ftmpl_array.h
 include/factory/templates/ftmpl_factor.h
@@ -128,6 +129,7 @@ include/singular/coeffs/gnumpc.h
 include/singular/coeffs/gnumpfl.h
 include/singular/coeffs/longrat.h
 include/singular/coeffs/modulop.h
+include/singular/coeffs/modulop_inl.h
 include/singular/coeffs/mpr_complex.h
 include/singular/coeffs/mpr_global.h
 include/singular/coeffs/ntupel.h
@@ -142,11 +144,13 @@ include/singular/kernel/GBEngine/f5data.h
 include/singular/kernel/GBEngine/f5gb.h
 include/singular/kernel/GBEngine/f5lists.h
 include/singular/kernel/GBEngine/janet.h
+include/singular/kernel/GBEngine/kChinese.h
 include/singular/kernel/GBEngine/kInline.h
 include/singular/kernel/GBEngine/khstd.h
 include/singular/kernel/GBEngine/kstd1.h
 include/singular/kernel/GBEngine/kstdfac.h
 include/singular/kernel/GBEngine/kutil.h
+include/singular/kernel/GBEngine/kverify.h
 include/singular/kernel/GBEngine/nc.h
 include/singular/kernel/GBEngine/ratgring.h
 include/singular/kernel/GBEngine/ringgb.h
@@ -187,6 +191,7 @@ include/singular/kernel/numeric/mpr_numeric.h
 include/singular/kernel/oswrapper/feread.h
 include/singular/kernel/oswrapper/rlimit.h
 include/singular/kernel/oswrapper/timer.h
+include/singular/kernel/oswrapper/vspace.h
 include/singular/kernel/polys.h
 include/singular/kernel/preimage.h
 include/singular/kernel/spectrum/GMPrat.h
@@ -241,10 +246,10 @@ include/singular/reporter/reporter.h
 include/singular/reporter/s_buff.h
 include/singular/reporter/si_signals.h
 include/singular/singularconfig.h
-lib/libSingular-4.1.3.so
+lib/libSingular-4.2.0.so
 lib/libSingular.a
 lib/libSingular.so
-lib/libfactory-4.1.3.so
+lib/libfactory-4.2.0.so
 lib/libfactory.a
 lib/libfactory.so
 %%NTL%%lib/libgfan-0.6.so
@@ -253,10 +258,10 @@ lib/libfactory.so
 lib/libomalloc-0.9.6.so
 lib/libomalloc.a
 lib/libomalloc.so
-lib/libpolys-4.1.3.so
+lib/libpolys-4.2.0.so
 lib/libpolys.a
 lib/libpolys.so
-lib/libsingular_resources-4.1.3.so
+lib/libsingular_resources-4.2.0.so
 lib/libsingular_resources.a
 lib/libsingular_resources.so
 libdata/pkgconfig/Singular.pc
@@ -552,11 +557,12 @@ share/ml_singular/extract.lib
 %%DATADIR%%/LIB/paraplanecurves.lib
 %%DATADIR%%/LIB/perf.py
 %%DATADIR%%/LIB/perron.lib
+%%DATADIR%%/LIB/pfd.lib
 %%DATADIR%%/LIB/phindex.lib
 %%DATADIR%%/LIB/pointid.lib
-%%DATADIR%%/LIB/poly.lib
 %%DATADIR%%/LIB/polybori.lib
 %%DATADIR%%/LIB/polyclass.lib
+%%DATADIR%%/LIB/polylib.lib
 %%DATADIR%%/LIB/polymake.lib
 %%DATADIR%%/LIB/presolve.lib
 %%DATADIR%%/LIB/primdec.lib
@@ -599,6 +605,7 @@ share/ml_singular/extract.lib
 %%DATADIR%%/LIB/spcurve.lib
 %%DATADIR%%/LIB/spectrum.lib
 %%DATADIR%%/LIB/standard.lib
+%%DATADIR%%/LIB/stanleyreisner.lib
 %%DATADIR%%/LIB/stratify.lib
 %%DATADIR%%/LIB/surf.lib
 %%DATADIR%%/LIB/surf_jupyter.lib