diff --git a/lang/python38/Makefile b/lang/python38/Makefile
index da6a5bfe9ad1e..ecc3e9ca22c16 100644
--- a/lang/python38/Makefile
+++ b/lang/python38/Makefile
@@ -48,13 +48,14 @@ PLIST_SUB=		ABI=${ABIFLAGS} \
 			XYZDOT=${PORTVERSION} \
 			OSMAJOR=${OSVERSION:C/([0-9]*)[0-9]{5}/\1/}		# For plat-freebsd* in pkg-plist. https://bugs.python.org/issue19554
 
-OPTIONS_DEFINE=		DEBUG IPV6 LIBFFI NLS PYMALLOC
-OPTIONS_DEFAULT=	LIBFFI PYMALLOC
+OPTIONS_DEFINE=		DEBUG IPV6 LIBFFI LIBMPDEC NLS PYMALLOC
+OPTIONS_DEFAULT=	LIBFFI LIBMPDEC PYMALLOC
 OPTIONS_RADIO=		HASH
 OPTIONS_RADIO_HASH=	FNV SIPHASH
 OPTIONS_SUB=		yes
 
 LIBFFI_DESC=		Use libffi from ports instead of bundled version
+LIBMPDEC_DESC=		Use libmpdec from ports instead of bundled version
 NLS_DESC=		Enable gettext support for the locale module
 PYMALLOC_DESC=		Enable specialized mallocs
 
@@ -71,6 +72,9 @@ IPV6_CONFIGURE_ENABLE=	ipv6
 LIBFFI_CONFIGURE_ON=	--with-system-ffi
 LIBFFI_LIB_DEPENDS=	libffi.so:devel/libffi
 
+LIBMPDEC_CONFIGURE_ON=	--with-system-libmpdec
+LIBMPDEC_LIB_DEPENDS=	libmpdec.so:math/mpdecimal
+
 # Use CPPFLAGS over CFLAGS due to -I ordering, causing elementtree and pyexpat
 # to break in Python 2.7, or preprocessor complaints in Python >= 3.3
 # Upstream Issue: https://bugs.python.org/issue6299
diff --git a/lang/python38/files/patch-Modules___decimal___decimal.c b/lang/python38/files/patch-Modules___decimal___decimal.c
new file mode 100644
index 0000000000000..4ea7b4f1b4ee1
--- /dev/null
+++ b/lang/python38/files/patch-Modules___decimal___decimal.c
@@ -0,0 +1,20 @@
+--- Modules/_decimal/_decimal.c.orig	2021-02-17 20:39:05 UTC
++++ Modules/_decimal/_decimal.c
+@@ -3284,7 +3284,7 @@ dec_format(PyObject *dec, PyObject *args)
+     }
+     else {
+         size_t n = strlen(spec.dot);
+-        if (n > 1 || (n == 1 && !isascii((uchar)spec.dot[0]))) {
++        if (n > 1 || (n == 1 && !isascii((unsigned char)spec.dot[0]))) {
+             /* fix locale dependent non-ascii characters */
+             dot = dotsep_as_utf8(spec.dot);
+             if (dot == NULL) {
+@@ -3293,7 +3293,7 @@ dec_format(PyObject *dec, PyObject *args)
+             spec.dot = PyBytes_AS_STRING(dot);
+         }
+         n = strlen(spec.sep);
+-        if (n > 1 || (n == 1 && !isascii((uchar)spec.sep[0]))) {
++        if (n > 1 || (n == 1 && !isascii((unsigned char)spec.sep[0]))) {
+             /* fix locale dependent non-ascii characters */
+             sep = dotsep_as_utf8(spec.sep);
+             if (sep == NULL) {
diff --git a/lang/python38/files/patch-setup.py b/lang/python38/files/patch-setup.py
new file mode 100644
index 0000000000000..7bd5deb4202a7
--- /dev/null
+++ b/lang/python38/files/patch-setup.py
@@ -0,0 +1,11 @@
+--- setup.py.orig	2021-05-03 09:47:56 UTC
++++ setup.py
+@@ -2051,7 +2051,7 @@ class PyBuildExt(build_ext):
+         undef_macros = []
+         if '--with-system-libmpdec' in sysconfig.get_config_var("CONFIG_ARGS"):
+             include_dirs = []
+-            libraries = [':libmpdec.so.2']
++            libraries = ['mpdec']
+             sources = ['_decimal/_decimal.c']
+             depends = ['_decimal/docstrings.h']
+         else: