diff --git a/sysutils/asmon/Makefile b/sysutils/asmon/Makefile
index 21027ea4a52c..bb2589087f7d 100644
--- a/sysutils/asmon/Makefile
+++ b/sysutils/asmon/Makefile
@@ -1,37 +1,41 @@
 # Created by: jack
 
 PORTNAME=	asmon
 PORTVERSION=	0.61
 PORTREVISION=	3
 CATEGORIES=	sysutils afterstep
 MASTER_SITES=	AFTERSTEP/apps/asmon
 
-MAINTAINER=	bofh@FreeBSD.org
+MAINTAINER=	ports@FreeBSD.org
 COMMENT=	Swallowable applet monitors the CPU usage, memory, and swap, etc
 
 LICENSE=	GPLv2
 
 BROKEN_FreeBSD_12=	fails to compile: read_mem.c: invalid use of undefined type 'struct vmmeter'
 BROKEN_FreeBSD_13=	fails to compile: read_mem.c: invalid use of undefined type 'struct vmmeter'
 BROKEN_FreeBSD_14=	fails to compile: read_mem.c: invalid use of undefined type 'struct vmmeter'
 BROKEN_mips=		fails to compile: asmon.c: storage size of 'sum' isn't known
 BROKEN_mips64=		fails to compile: asmon.c: storage size of 'sum' isn't known
 
-BUILD_WRKSRC=	${WRKDIR}/${PORTNAME}-${PORTVERSION}/asmon
-CFLAGS+=	-I${LOCALBASE}/include
+DEPRECATED=	Fails to build on modern FreeBSD
+EXPIRATION_DATE=	2021-12-27
+
 USES=		gmake xorg
 USE_CSTD=	gnu89
 USE_XORG=	xpm x11
+
+BUILD_WRKSRC=	${WRKDIR}/${PORTNAME}-${PORTVERSION}/asmon
+CFLAGS+=	-I${LOCALBASE}/include
 ALL_TARGET=	asmon
 MAKE_ARGS+=	LIBDIR="-L${LOCALBASE}/lib" \
 		SOLARIS_LIBS=-lkvm
 
 PLIST_FILES=	"@(,kmem,) bin/asmon"
 
 post-patch:
 	${REINPLACE_CMD} -e 's:gcc:${CC} ${CFLAGS}:' ${BUILD_WRKSRC}/Makefile
 
 do-install:
 	${INSTALL_PROGRAM} ${WRKSRC}/asmon/asmon ${STAGEDIR}${PREFIX}/bin
 
 .include <bsd.port.mk>
diff --git a/sysutils/asmon/files/patch-asmon-asmon.c b/sysutils/asmon/files/patch-asmon-asmon.c
index 7fce50d6a099..39f0e813e1a6 100644
--- a/sysutils/asmon/files/patch-asmon-asmon.c
+++ b/sysutils/asmon/files/patch-asmon-asmon.c
@@ -1,15 +1,11 @@
---- asmon/asmon.c.bak	2012-03-13 19:03:06.795252708 +0600
-+++ asmon/asmon.c	2012-03-13 19:04:16.395242371 +0600
-@@ -990,7 +990,11 @@
+--- asmon/asmon.c.orig	2000-07-20 11:08:47 UTC
++++ asmon/asmon.c
+@@ -990,7 +990,7 @@ void DrawXmem(int Xpid, float total) 
  
  	kproc = kvm_getprocs(kd, KERN_PROC_PID, Xpid, &kcnt);
  
 -	Xsize = kproc->kp_eproc.e_vm.vm_map.size / 1024;
-+	#if __FreeBSD_version < 500000
-+		Xsize = kproc->kp_eproc.e_vm.vm_map.size / 1024;
-+	#else
-+		Xsize = kproc->ki_size / 1024;
-+	#endif
++	Xsize = kproc->ki_size / 1024;
  #endif
          if(old_Xsize!=Xsize)
  	{